Cold Email vs Spam in 2026: The New Rules of Deliverability & Compliance

Introduction

Cold email can be a B2B sales powerhouse – when done correctly. However, as we move into 2026, the line between a well-targeted cold email and unwanted spam is thinner than ever. Nearly half of all emails sent worldwide are considered spam (5), and email providers are using increasingly sophisticated filters to protect inboxes. This comprehensive guide will help sales and marketing leaders navigate the new rules of cold email deliverability and compliance. We’ll clarify cold email vs spam, highlight evolving laws, and share actionable best practices to ensure your outreach lands in inboxes – not in junk folders.

Why does this matter? Studies show cold outreach remains highly effective – sales teams rate cold email 40% more effective than social channels for acquiring new customers (3). But to tap that potential, you must avoid the spam trap. Read on to learn how to craft compliant, high-deliverability cold email campaigns that drive results (and how our expertise in omnichannel outbound sales can help augment your success).

What’s the Difference Between Cold Email and Spam?

At first glance, a cold email and a spam email might both be unsolicited messages landing in a stranger’s inbox. But cold email and spam are not the same. The differences come down to intent, relevance, personalization, and compliance (1):

• Intent & Targeting: A legitimate cold email has a clear business purpose and targets a specific, relevant recipient. It’s sent one-to-one (even if using automation) with a tailored message for that person or role (1). Spam, on the other hand, is all about indiscriminate volume. Spammers blast out emails to as many addresses as possible, often without any regard for relevance (1).
  
• Value & Personalization: Good cold emails are intentional and value-driven, focusing on the recipient’s needs or pain points (3). They often reference something specific – like the prospect’s company, industry, or a trigger event – showing research and personalization. Spam emails are generic, purely product-centric “push” messages sent with a spray-and-pray approach (3). If an email provides zero value or context for the reader, it’s likely to be perceived as spam.
  
• Sender Identity & Transparency: Real cold outreach comes from a legitimate sender (a real person and company). It uses an accurate sender name and email address, often with a proper business domain and signature. It should be immediately clear who is contacting the recipient and why. Spam emails frequently obscure or fake the sender’s identity with misleading “from” names or domains (1).
  
• Opt-Out & Compliance: Legitimate cold emails include an easy way to opt out or unsubscribe, and they honor consent rules. Even in B2B contexts where prior consent isn’t always required, ethical senders give recipients a clear choice to decline further emails (1). Spam emails typically lack a working unsubscribe link or any permission safeguards (1). Spammers often ignore laws like CAN-SPAM, GDPR, or other anti-spam regulations, whereas responsible cold emailers follow them (more on these laws below).
  
• Infrastructure & Sending Practices: Behind the scenes, professional cold email outreach uses proper infrastructure – authenticated domains (with SPF, DKIM, DMARC), warmed-up sending IPs/domains, and sensible send rates (1). Spammers usually rely on cheap mass-mail tools, throwaway accounts or free webmail addresses, and purchased lists of emails (1). These sloppy practices lead to high bounce rates, spam flags, and domain blacklisting.
  

Below is a quick comparison table summarizing cold email vs spam:

When does a cold email become spam?

A cold email becomes spam when it’s irrelevant, non-personalized, sent without permission, or lacks an opt-out. If it’s part of a bulk blast to unknown recipients, uses misleading subject lines, or ignores regulations, it’s likely to be flagged as spam.

Cold emails are legitimate business outreach – unsolicited, yes, but respectful and relevant. Spam is unsolicited junk – sent with a selfish agenda, no personalization, and often in violation of policies. As one expert puts it, the difference is ultimately in the eye of the beholder: if your message provides no clear value or context to the recipient, they’ll likely see it as spam (3). Always put yourself in the recipient’s shoes – if a cold email doesn’t earn its place in their inbox, it’s veering into spam territory.

The 2026 Deliverability Landscape: New Challenges & Rules

Getting a message into someone’s inbox isn’t as simple as hitting “send” – and it’s only becoming more complex. Email providers like Google and Microsoft have turned the dial up on their spam filters. Deliverability – the ability of your email to land in the inbox rather than “bounce” or get filtered as spam – is now influenced by a wider array of factors than ever before.

In 2026, email deliverability is both a science and an art (4). Yes, the technical “science” (authentication, server configuration, etc.) is critical – but the “art” of how you craft and send your message plays an equally important role. Here are the key deliverability factors and trends to understand:

• User Engagement Signals Are King: Modern spam filters heavily factor in how recipients interact with your messages. Open rates, reply rates, delete-without-reading rates, and spam complaint rates all feed into your sender reputation (4). For instance, Gmail and Yahoo closely track spam complaints – as a rule of thumb, keep spam reports below 0.1% (1 complaint per 1,000 emails) to stay in good standing (9). A single recipient clicking “Report Spam” doesn’t just hurt that email – it lowers your domain’s reputation, making it more likely your future emails to anyone will land in junk (1). Low engagement (few opens/replies) also flags to providers that your emails might not be wanted. The bottom line: If people aren’t engaging positively, deliverability will decline.
  
• Smarter Spam Filters (AI & Machine Learning): The era of simple keyword-based spam filters is over. In 2026, inbox providers use AI to analyze email content and sending patterns for “spamminess.” Filters look at your email’s tone, structure, and even emotional language to judge authenticity (4). They can tell if you’re blasting a templated pitch versus writing a human message. Intent and authenticity matter – algorithms are effectively asking, “Does this email sound like a one-to-one human communication, or a mass marketing blast?” If it’s the latter, expect the spam folder. This means clever tricks to evade filters (like changing “Free offer” to “Fre off3r”) are obsolete* – AI sees right through them. Instead, focusing on sincere, relevant content is the only sustainable path (more on content best practices later).
  
• Stricter Technical Requirements: Email service providers have raised the bar on technical compliance. Proper email authentication – SPF, DKIM, and DMARC – is now a must for any business sender. These DNS settings prove you are who you say you are (SPF/DKIM) and give receivers instructions to reject unauthorized use of your domain (DMARC). If you haven’t set these up, your cold emails will almost certainly be blocked or flagged regardless of content (1). Additionally, for high-volume senders, including a List-Unsubscribe header (one-click opt-out) is becoming standard – Gmail, for example, will prompt users to unsubscribe if they see a newsletter-style email without an easy opt-out (1). Tip: Check that your cold email platform automatically inserts an unsubscribe link or header in your cold emails; if not, add one manually to avoid deliverability penalties.
  
• Volume and Sending Patterns: How many emails you send, and how quickly, directly impacts deliverability. Suddenly sending thousands of emails from a new domain or IP is a huge red flag. Gradual “warming up” of your sending volume is now standard practice. For example, instead of blasting 1,000 emails on day one, you might start with 20-50/day and slowly ramp up over several weeks. Consistency and moderation are key – mailbox providers watch for unusual spikes in volume from your domain. In fact, new guidance in 2025-2026 is shifting away from the old “batch and blast” schedules. Varying your send times and not sending the exact same volume at the same time every day can appear more human and less bot-like (4). Translation: don’t always send 100 emails at 9:00 AM each Tuesday – mix it up a bit, which looks more organic (4).
  
• Domain Reputation Management: Businesses are increasingly treating their sending domains as a precious asset. Your domain’s reputation is like a credit score for your emails – and bad choices can ruin it. Many teams now use dedicated domains or subdomains for cold outreach to protect their primary corporate domain’s reputation. For instance, if your company domain is yourcompany.com, you might send cold emails from yourcompany-leads.com or get.yourcompany.com. This way, if that domain gets a bad rep, your main domain isn’t as affected. However, even with a separate domain, the new rule is to build “domain equity” through responsible sending, not to burn and churn domains (4). In the past, some spammers would buy multiple domains, warm them artificially, then blast until they were blocked and move on. Today, domains that show genuine positive engagement over time are rewarded, and simply rotating domains can’t fully fool the sophisticated algorithms (4). Focus on one or a few domains you can maintain quality on, rather than a high-turnover domain strategy.
  
• The Rise of Omnichannel Outreach: Another trend affecting cold email perception is the use of omnichannel sequences. Savvy sales teams combine email with LinkedIn touches, phone calls, and other channels. When a prospect has seen your LinkedIn connection request or heard a voicemail, your cold email can feel warmer and more expected. This multi-touch approach isn’t directly a technical deliverability factor, but it improves recipient perception – which can indirectly reduce spam complaints. Martal Group, for example, employs an omnichannel marketing strategy in its campaigns, combining targeted cold emails, cold calls, and LinkedIn outreach to increase engagement while preventing channel fatigue. The result is prospects are less likely to be bewildered by a “random” email and more likely to respond positively.
  

What are the biggest deliverability risks for cold email campaigns?

There are several common pitfalls that can hurt your email performance and sender reputation:

• Sending from a new or unauthenticated domain
• Using purchased or unverified lists
• High bounce or spam complaint rates
• Ignoring opt-out requests
• Sending with spammy language or design-heavy templates

Being aware of these risks and taking steps to avoid them can help ensure your emails reach the right inboxes and generate better results.

In 2026, getting into the inbox requires a holistic approach. You need the technical fundamentals in place and a strategy that emphasizes quality over quantity. Think of mailbox providers as gatekeepers using thousands of data points to judge your emails – from authentication records to how recipients interact with your last 10 sends. By understanding these new rules of deliverability, you can adjust your cold email program to meet modern standards (and significantly boost your response rates).

Cold Email Compliance: Laws and Regulations You Must Know

One person’s “harmless sales email” is another regulator’s “unsolicited commercial message.” 

Is cold emailing legal?

Yes, cold emailing is legal in many countries, if done properly. The legality of cold emailing varies across regions, and failing to comply can result in severe penalties (fines, or even being barred from sending). 

In the U.S., it’s allowed under CAN-SPAM if emails include sender info, an unsubscribe link, and aren’t misleading. Other countries like Canada or EU nations have stricter requirements, often needing consent or “legitimate interest.”

How do different countries regulate cold email vs spam?

Here we break down the key email laws in the U.S. and internationally that govern cold outreach:

United States: CAN-SPAM Act (and FTC Rules)

In the U.S., cold emailing is legal as long as you follow the rules. The main law is the CAN-SPAM Act (Controlling the Assault of Non-Solicited Pornography and Marketing Act of 2003), which sets the ground rules for commercial emails (3). Unlike in some countries, you do not need prior consent or an “opt-in” to send B2B cold emails in the U.S. – provided you comply with CAN-SPAM. Key CAN-SPAM requirements include (2) (3):

• Truthful “From” and “Subject” Lines: You must accurately identify yourself in the email header. No spoofed email addresses or fake names. The subject line must not be deceptive about the content (3) (e.g., don’t write “Re: Our Meeting” if you’ve never met – that’s considered misleading).
  
• Identify the Message as an Ad: CAN-SPAM requires that commercial emails include a clear indication they are an advertisement or solicitation. This doesn’t mean you need “ADV” in the subject, but somewhere in the content it should be evident that the email is a sales/marketing outreach, not a personal note.
  
• Include a Physical Address: Every email must include the sender’s valid physical postal address (your company’s mailing address or PO Box) (3). This is typically placed in the footer.
  
• Easy Unsubscribe Mechanism: You must give recipients a clear, easy way to opt out of future emails (3). Usually this is a clickable “unsubscribe” link. It can also be instructions to reply with “Unsubscribe” – but a one-click link is best practice. The opt-out mechanism has to be functional for at least 30 days after sending the email.
  
• Honor Opt-Out Requests Promptly: If someone asks to be removed, you must stop emailing them within 10 business days (3). Moreover, you cannot sell or transfer their email to another list (except for compliance purposes, like a suppression list). Continuing to email someone who opted out is a direct violation.
  
• Liability for Third-Party Senders: If you hire a sales agency or use a third-party email platform to send your cold emails, your company is still legally responsible for compliance (3). Both the company whose product is being promoted and the company sending the email can be held accountable for any CAN-SPAM breaches.
  

Non-compliance with CAN-SPAM can lead to hefty penalties – up to $53,088 (10). The FTC has pursued companies for spam violations, so this is not just theoretical. The good news is that CAN-SPAM’s rules are straightforward. In short: identify yourself, don’t lie in your email, and give people a way to say “no thanks”. Do that, and you’re on solid ground in the U.S.

European Union (and UK): GDPR & ePrivacy Directive

If your prospects are in the EU (or UK), the rules tighten. Europe’s regulations reflect a philosophy of privacy and consent first. Two major frameworks apply to cold emails in Europe:

• GDPR (General Data Protection Regulation): Primarily a data privacy law, GDPR affects how you store and use personal data (including someone’s work email, since it can identify an individual). Under GDPR, you need a legal basis to process someone’s personal data – for marketing emails, the relevant bases are typically “consent” or “legitimate interest.” If you’re emailing an individual at their personal email (especially B2C), explicit prior consent (opt-in) is usually required. For B2B contacts at their company email, some EU countries allow cold email under “legitimate interest,” but you must be able to justify that your outreach is relevant to their job role and that it wouldn’t surprise or offend them. GDPR also requires that you inform people how you got their data if they ask, and that you honor requests like deletions or objections.
  
• ePrivacy Directive (aka PECR in the UK): This is a specific set of rules for electronic communications. Most EU countries have laws (often called “anti-spam” laws) implementing the ePrivacy Directive. These generally require opt-in consent for unsolicited email to natural persons (individuals). However, many countries have a softer stance for B2B email to corporate addresses. For example, the UK’s PECR allows B2B cold emails to company addresses without prior consent, as long as the email is relevant to the recipient’s job and you give an opt-out option (1). Key point: Even where B2B cold email is allowed, you must still identify yourself clearly and include an unsubscribe link (1). If someone asks you to stop, you must not email them again.
  

In practice, for EU/UK best practice: focus on highly targeted B2B emails that you can defend as beneficial to the recipient’s work. Always include an opt-out, and maintain a suppression list of anyone who objects (to avoid contacting them again) (1). Steer clear of emailing EU individuals at their personal Gmail/Yahoo addresses unless they opted in. And remember, GDPR means you should be able to demonstrate why you’re emailing someone – e.g. you found their business contact info on their company’s site and you believe your offering genuinely addresses a business need they may have (that’s a “legitimate interest” rationale).

Violating EU/UK email rules can trigger fines, though typically less explicit than CAN-SPAM’s per-email fines. GDPR allows penalties up to €20 million or 4% of global turnover for serious infractions, and EU data authorities have fined companies for improper marketing emails (usually in the tens or hundreds of thousands of euros). The UK’s ICO and other regulators can issue penalties if you send mass unsolicited emails without a valid basis. In short, Europe takes unsolicited email seriously, so when in doubt, get permission or stick to very relevant B2B outreach only.

Canada: CASL (Canadian Anti-Spam Legislation)

Canada’s anti-spam law (CASL) is known as one of the toughest. CASL requires consent (express or implied) before sending commercial email to Canadians, with very few exceptions (1). “Express” consent means the person explicitly agreed (e.g. checked a box or signed up). “Implied” consent covers situations like an existing business relationship or someone who gave you their card and didn’t object to emails. If you’re purely cold-emailing a list of prospects in Canada with no prior relationship, you’re likely outside CASL’s allowances.

Key CASL requirements:

• Consent First: Unless you have a qualifying implied consent, you should only email people who have opted in. Cold prospecting is risky under CASL unless you can justify implied consent (for instance, if the person’s email was conspicuously published and your message relates to their role – a narrow exception).
  
• Identification: You must identify the sender and any partners clearly, similar to CAN-SPAM’s truthful header requirement.
  
• Unsubscribe: Every email must include a clear unsubscribe mechanism (and you must remove opt-outs within 10 business days).
  
• Record-Keeping: It’s wise to keep records of how/when you obtained consent for each contact in Canada, in case of audits.

How do you obtain permission or “implied consent” for cold emailing?

Implied consent can exist if:

• You have a prior business relationship
• The contact’s email was published publicly for business use
• You provide a clear, relevant message and opt-out
  Explicit consent involves the recipient opting in, usually via a form or verbal agreement.

CASL violations carry severe penalties – up to $1 million (CAD) per violation for individuals and $10 million for companies (8). In practice, the Canadian regulator has indeed issued multi-million dollar fines to businesses for spamming. So, if Canada is in your market, you either need to invest in obtaining consent (perhaps via LinkedIn or calls first), or tread very carefully under the implied consent exceptions. Many companies simply exclude Canada from pure cold email campaigns or use channel partners who have lists of opt-in Canadian prospects.

Other Regions

Globally, anti-spam laws vary, but the general trend is toward opt-in regimes. Countries like Australia, New Zealand, and many in Asia-Pacific also prohibit unsolicited marketing emails without prior consent (with some B2B nuances). If you plan to email prospects in a country, always check that country’s spam laws. For instance, Australia’s Spam Act requires explicit consent (no B2B exception), and violations can incur fines. The safest approach if you’re reaching out internationally is to apply the strictest common denominator: include identification and unsubscribe info in every email, and when in doubt, get permission or ensure the email is clearly a fit for the recipient’s business interests.

Key Compliance Takeaway: Cold emailing can be done legally almost everywhere if you follow the rules. Always disclose who you are, never mislead recipients, and give them a one-click way to stop emails (1). Treat personal data with respect (GDPR) and keep proof of consent where required. By designing your campaigns with compliance in mind, you not only avoid fines, but you also build trust with prospects – showing you respect their boundaries.

(Disclaimer: The above is for general informational purposes and not legal advice. Consult a legal professional for specifics on compliance.)

What Key Best Practices Help a Cold Email Avoid Spam Filters?

Understanding the rules and differences is half the battle – now it’s time to apply best practices so your cold emails actually reach the inbox and get positive responses. Below we cover actionable tactics for improving deliverability and avoiding the spam folder, from technical setup to content strategy. These tips will help protect your sender reputation and boost email performance:

1. Set Up Proper Email Infrastructure and Authentication

Think of this as laying a solid foundation for your cold email program. Before sending a single campaign, do the following:

• Use a Custom Sending Domain: Don’t blast cold emails from your main corporate domain (and definitely not from a free Gmail/Yahoo account). Instead, set up a dedicated domain or subdomain (e.g., yourcompany-outbound.com or sales.yourcompany.com). This contains any reputation fall-out. Pro tip: Warm up this domain gradually by sending a low volume at first and ramping up over a few weeks to build trust.
  
• Implement SPF, DKIM, and DMARC: These email authentication protocols are essential in 2026. SPF is a DNS record listing which servers are allowed to send email for your domain. DKIM adds a digital signature to your emails to verify they weren’t tampered with. DMARC ties it together and gives receivers policies on how to handle unauthenticated mail. Ensuring all three are correctly configured will significantly boost your chances of passing spam filters (1). Many inbox providers outright reject or flag emails from domains without these. Use free tools (like MXToolbox or your email service’s tools) to test your SPF/DKIM alignment.
  
• Warm Up Your Email Account (Mailbox): If you’re using a new email address or a new domain, don’t go zero-to-100. Send a trickle of emails initially. You can also leverage automated warm-up tools or services that gradually increase sending volume and even simulate engagement (some tools have networks that “open” and “reply” to your emails to train inbox algorithms). While some debate the efficacy of automated warm-up, a controlled send ramp-up is definitely important. Start with maybe 20-50 emails/day, then increase by ~10-20 per day as long as you aren’t seeing deliverability issues. Martal Group’s deliverability team, for example, warms up custom domains and mailboxes for clients to protect sender reputation, ensuring that large campaigns don’t start from a cold start (6).
  
• Use a Quality Email Sending Service: If you’re sending via your normal Gmail/Outlook, be cautious – those have sending limits and aggressive internal filters for bulk sends. Consider a reputable email automation platform or SMTP service that is cold-email friendly. Ensure they have good deliverability features (custom tracking domains, feedback loop processing, etc.). Always send yourself test emails to see if they land in Spam or Promotions tab, and adjust accordingly.
  
• Monitor Domain and IP Reputation: Regularly check your domain’s health. Google Postmaster Tools (for Gmail) is invaluable – it shows your domain reputation as seen by Google. Also, keep an eye on blacklists (MXToolbox blacklist check can scan major ones). If you do get blacklisted (e.g., by Spamhaus), pause and resolve it before continuing. Maintaining a “green” reputation score means emails are far more likely to be delivered.

2. Craft Email Content That Feels Personal, Not Spammy

No matter how solid your technical setup, poor email content can trigger spam filters or manual spam reports. When writing cold emails in 2026, make them look and read like a one-to-one message from a professional to a professional:

• Personalize Beyond the Basics: It’s not enough to insert <First Name> and <Company> and call it a day. Include insights that show you researched the prospect – e.g. a recent news about their company, a pain point typical for their industry, or a mutual connection. The email body should make it clear why you chose to contact them. This level of relevance differentiates a cold email from a form spam. As one outreach expert noted, “cold emails require researching the recipient to make sure the message is actually valuable to them” (3). In contrast, spam “doesn’t matter who the recipient is” (3) – so prove that you do care who the recipient is.
  
• Write a Clear, Honest Subject Line: Avoid clickbait or misleading subjects at all costs – they may get an open, but they also breed distrust and spam reports. Instead, use something straightforward and relevant, e.g. “Idea for [Prospect’s Company] – [One-liner hint]”. If your subject implies urgency or a question, make sure the email delivers on that. Remember, if the subject line and email body don’t match or seem disconnected, recipients feel tricked and may hit “Report Spam” (1). Also, steer clear of ALL CAPS or excessive punctuation!!! – these are classic spam signals.
  
• Keep the Format Simple: A cold sales email is not the place for heavy HTML, tons of images, or fancy sales email templates. A mostly plain-text email with perhaps one small graphic (or your email signature logo) is best. Too many images or graphics can trigger spam filters and also look promotional (3). Likewise, avoid large attachments – if you need to share content, use a link (but see link caution below). The email should feel like a personal note, not a marketing newsletter.
  
• Mind Your Language (Literally): Certain phrases can still trip content filters. Obvious spam words like “free money”, “act now!!!”, “win big” etc., are red flags. But in B2B, it’s more about overall tone. Overly salesy language (“increase your revenue 10x!!!”) can hurt. Also, avoid excessive use of exclamation points or shouting in text (3). One exclamation for enthusiasm is fine; five looks like spam. Maintain a professional tone – conversational but respectful.
  
• Include a Polite Closing and Signature: Always have a professional email signature with your name, title, company, and contact info (including that physical address for CAN-SPAM). Not only is this legally needed, it also reassures the recipient that you’re a legitimate businessperson, not a scammer lurking in the shadows. And as mentioned, always include the unsubscribe option clearly (usually as a line like “Click here to unsubscribe” or “If you prefer not to receive emails, let me know”). It might feel counter-intuitive in a one-to-one style email, but it’s required in many jurisdictions and even where not, it can save you from a spam report by giving the prospect a less harsh way to opt out (1).
  
• Limit Links and Trackers: Be careful with how many links you include. A cold email loaded with hyperlinks (especially tracking parameters) can look phishy. Stick to one, or at most a couple, of links – for example, a link to your company website or a calendar booking link. If using open tracking pixels or link tracking (common in sales email tools), use a custom tracking domain if possible so the tracked links use your domain (e.g. link.yourcompany.com) – this looks more trustworthy than generic tracking links. And avoid URL shorteners like bit.ly in cold emails; spammers use them, so they can hurt trust.

How much personalization turns a cold email into something not spam?

At minimum, include the recipient’s name, company, and contextually relevant messaging. Effective personalization involves referencing their role, industry, or recent business activity. Shallow mail merges aren’t enough—your email must feel research-backed and role-specific to stand out as legitimate.

By focusing on personalization and clarity in your content, you not only avoid spam filters – you also increase the chances the reader will respond. Remember, the recipient’s perception defines spam: if they feel your email is a mass blast or irrelevant, they’ll ignore or report it. If it reads like a thoughtful, targeted message, they’re far more likely to engage.

3. Optimize Your Sending Strategy (Timing, Cadence, and Lead Segmentation)

Even with great content and setup, you can sabotage deliverability by how you send. Here’s how to strategically manage your sending:

• Send at a Human Pace: Don’t fire off 500 emails in one minute. Sending too many emails too fast from one account can trigger rate limiting or spam flags. Stagger your sends over time. Many tools let you randomize send times (e.g., 8-12 emails per hour instead of 100 at once). This mimics a human sender and avoids overload on recipient mail servers. Also, consider the timing in the recipient’s time zone – hitting someone’s inbox at 2 AM their time isn’t ideal for response or perception.
  
• Right-Size Your Cadence (Follow-Up Schedule): Cold outreach often involves sending a sequence of email follow-ups if no response. But be careful – too frequent follow-ups can irritate prospects and lead to spam reports. Instead of emailing every day or every other day, give more breathing room. For example, a common best practice is 4-7 days between touches. Recent deliverability advice suggests lengthening email cadences in 2025/2026 (1). One study suggests for small business prospects, consider 2-4 emails total over ~30 days; for mid-market, maybe 3-6 emails over 30-60 days; for enterprise, possibly 5-9 touches over 60+ days (1). In short, adjust to your audience – a startup founder’s inbox might handle more follow-ups than a Fortune 500 exec’s, but err on the side of polite persistence, not pestering. And if you do include multiple follow-ups, make sure each provides additional value or context (don’t just send “Did you get my last email?” four times).
  
• Monitor Engagement and Prune Unresponsive Contacts: Pay attention to who is opening or replying, and who isn’t. Continuing to email someone who never engages after many attempts can hurt your reputation. Implement rules to drop or “sunset” leads that show zero engagement after a certain number of touches. For instance, you might decide: if after 4 emails a prospect hasn’t opened or replied, remove them from the sequence (or at least pause for a few months) (1). This keeps you from racking up sends to people who will likely never respond – and it lowers the chance of annoying them into a spam complaint. Many sales engagement platforms can automate this by branching sequences or marking “cold” leads to exclude.
  
• Limit Emails to the Same Company: If you’re targeting multiple people at one company, be careful not to email too many colleagues at once. If five employees at the same small company all get what looks like a canned email, it raises internal red flags and could spark spam reports (or email-forwarding that makes your approach look bad). A good rule is to cap outreach to a single company to a handful of contacts at a time. For example, you might choose at most 1 active contact at a small company, 2-3 at a mid-sized, maybe up to 5 at a large enterprise, during the same outreach period (1). If one person bounces or never responds, then you can try another after some delay. This “surround sound” approach must be done tactfully.
  
• Use Dedicated Sending Personas: It can help to have a specific sender identity for cold outreach (e.g., your outbound SDR or AE’s email account), separate from your newsletters or customer emails. That way, any reputation issues with cold email don’t spill over to your other communications. Also, people are more likely to engage with an individual’s email (e.g. [email protected]) than a generic marketing address ([email protected]). Make that persona accessible and responsive – if someone replies, they should get a prompt human response, not silence. Engaged replies actually boost your sending reputation.
  
• Track and Adjust: Treat each cold email campaign as an experiment. Keep an eye on metrics: delivery rate, open rate, reply rate, bounce rate, and complaint rate. If you see a spike in bounces or complaints, stop and diagnose. Maybe your list source was poor (lots of invalid addresses) – time to verify your list. Or maybe a particular email in your sequence has wording that upsets people – rewrite it. High unsubscribe rates or low opens might indicate your targeting is off or your subject lines need work. By iterating, you’ll improve both outcomes and deliverability.

4. Maintain Pristine List Quality and Targeting

Good deliverability actually starts before you send – with whom you choose to email. Quality over quantity is the mantra:

• Build (or Buy) Lists Wisely: The worst thing you can do is purchase a giant list of “leads” from a sketchy provider and blast it. Those lists often contain spam traps, outdated addresses, or people who never agreed to be contacted – a recipe for bounces and complaints. Instead, build your lead lists through research or reputable data sources. If you do use a list vendor, use one that sources data ethically and conducts email list cleaning. Consider using intent data or buying signals (like job changes, funding events, tech stack info) to target the hottest prospects rather than cold contacts en masse (4). Martal Group, for example, emphasizes intent-driven, outbound prospecting – leveraging real-time signals and research to focus on contacts who are likely searching for your solution (7). This means your emails are more likely to be welcomed.
  
• Verify Email Addresses: Use an email verification tool to prune out invalid addresses before you send. Bounces not only waste your time – they hurt your sender reputation. High bounce rates signal you’re emailing a bad list (spam filters take note). A quick verification pass (via tools like NeverBounce, ZeroBounce, etc.) will catch typos and dead emails so you can remove them. Aim for a bounce rate under 2%.
  
• Avoid Spam Traps: Spam traps are addresses used by ISPs or blacklists to catch spammers – often old addresses that should never receive mail. The best way to avoid them is to never use old, scraped, or purchased lists of unknown origin. If you’re building a list from the web, be cautious – don’t harvest emails in bulk indiscriminately. Also, emailing role-based addresses like “[email protected]” or “[email protected]” can be riskier (they could be monitored or be aliases that nobody checks but spamtrap systems do). Focus on named individuals when possible.
  
• Segment and Personalize by Segment: If you sell to multiple industries or roles, segment your campaigns for relevance. For example, your cold email to a CFO should probably highlight different pain points than one to a Head of Sales. By segmenting and customizing your messaging per segment, you increase relevance which leads to better engagement (and fewer spam reports). Segmenting can also mean separating your mail streams: some companies use different domains or IPs for different product lines or regions, so an issue in one area doesn’t cascade to all emails.
  
• Keep Your Data Fresh: Don’t continuously email contacts who haven’t responded for years. Stale data leads to more bounces (people change jobs, etc.) and uninterested recipients. Periodically scrub your database. For long sequences, if a lead hasn’t engaged in 6 months or a year, consider a “break” or re-validation before more outreach. Some organizations even implement double opt-in for their inbound leads and use that as a quality control for any cold outreaches (3) – while that’s not typical for pure outbound, the underlying principle is ensure the people you email actually might want to hear from you.

By focusing on sending to clean, well-targeted lists, you dramatically tilt the odds in your favor. You’ll experience higher open and reply rates, which further enhance your sender reputation – a virtuous cycle.

5. Be Quick to Honor Opt-Outs and Feedback

This is both a compliance necessity and a deliverability booster: always respect the wishes of your email recipients.

• Make Unsubscribing Painless: Don’t hide the unsubscribe link in a tiny font or make people log in to unsubscribe. A prominent one-click unsubscribe not only keeps you legal, it also saves many relationships. A prospect who easily unsubscribes today might still have a neutral or positive view of your brand, whereas one who can’t find the unsubscribe and keeps getting emails will mark you as spam out of frustration (1). It’s better to lose them from the list than to get a spam report. Gmail, Outlook, and others also notice if users frequently skip your unsubscribe and report spam instead – not a good sign.
  
• Process Opt-Outs Immediately: If someone clicks “unsubscribe” or replies asking to be removed, ensure your system or team removes them fast. Under CAN-SPAM you have 10 business days, but in practice it should be much quicker (immediately, if possible) (3). Failing to remove and accidentally emailing them again virtually guarantees a spam report or a very annoyed reply.
  
• Pay Attention to Replies – Even Negative Ones: Not every response will be a positive lead. Some prospects might reply “Not interested” or “Don’t email me again.” Treat these like opt-outs – politely acknowledge and remove them from future sends. Do not attempt to convince someone who clearly asked to stop. This is crucial for compliance (especially in regions like EU with “right to object”) and it’s just good business manners.
  
• Monitor Spam Complaints: Many sending platforms provide feedback loop data – meaning if someone on a major ISP (like Yahoo, Outlook.com) marks you as spam, you can get notified. Keep an eye on those. If you see complaints coming in, evaluate what’s causing them. Perhaps a particular segment is not responding well, or an email template is misleading. Reducing whatever is driving complaints will directly improve deliverability.
  
• Have a Reply Management Plan: Cold emails can sometimes get replies like “Who are you and how did you get my email?!” or questions about your product. Respond to them promptly and professionally. Engaging replies (even unsubscribe requests answered politely) show mail providers that real conversations are happening – which can improve your reputation. Conversely, if prospects email back and get no response, they might sour on your company and mark future messages as spam.

In summary, respecting your recipients’ choices isn’t just ethical – it’s a core part of a sustainable cold email strategy. By building a “clean” sending reputation – low bounces, low complaints, quick opt-out compliance – you signal to Google, Microsoft, and others that you’re a responsible sender. This keeps the gatekeepers happy and your messages flowing to inboxes.

Cold Email vs. Spam. Deliverability Done Right

Ready to supercharge your cold email outreach? Achieving high deliverability and compliance can be complex – but you don’t have to tackle it alone. Martal Group is an experienced outbound lead generation partner that specializes in omnichannel outbound campaigns. We provide Sales-as-a-Service teams on demand to help you reach your dream clients through targeted cold email, cold calling, and LinkedIn outreach. Our experts handle everything from sourcing qualified B2B contacts to crafting personalized messaging and managing the technical groundwork (domain setup, warm-up, and ongoing deliverability monitoring). We also offer dedicated appointment setting services to fill your calendar with sales meetings and full sales outsourcing options for scalable pipeline growth. With over a decade of success in outbound sales, Martal knows how to execute compliant, high-performing campaigns that turn cold emails into warm sales leads.

Don’t let your messages get lost in spam – let’s ensure your story reaches the inbox. Book a free consultation with Martal Group today to elevate your outbound strategy and start generating more qualified leads. We’ll help you navigate the new rules of cold email deliverability and drive predictable revenue growth through smarter outreach.

References

1. Allegrow
2. Woodpecker
3. UserGems
4. Postbox Services
5. AgainstData
6. Martal Group  – Cold Email Lead Generation Service
7. Martal Group – Intent-Based Marketing
8. Borden Ladner Gervais
9. ActiveCampaign
10. Federal Trade Commission