Cold Email Compliance Guidelines: A Clear Guide

Laptop and document on a desk for reviewing cold email compliance guidelines.

Your prospect list probably isn't limited to one city or even one country. In today's connected world, you might be emailing someone in California one minute and someone in Germany the next. This global reach creates a new layer of complexity, as you have to consider different laws like the CCPA in the U.S. and GDPR in the EU. Juggling these different requirements can feel like a huge challenge, but it doesn't have to be. By adopting a strategy built on the highest standards, you can create a universally safe approach. This guide will walk you through the key cold email compliance guidelines for staying on the right side of the law, no matter where your contacts are located.

Key Takeaways

Treat compliance as your best defense: Following email laws like CAN-SPAM and GDPR is the most effective way to protect your sender reputation, avoid expensive fines, and ensure your messages are viewed as legitimate by inbox providers.
Nail the non-negotiable basics in every email: No matter who you're emailing, every message must clearly identify who you are, provide an honest subject line, and include a simple, obvious way for recipients to opt out.
Turn compliance into a system, not a task: Create a documented and automated process for verifying contacts, managing unsubscribe requests, and keeping records to reduce human error and make compliance a consistent part of your workflow.

What is Cold Email, and Why Should You Care About Compliance?

Cold email is the practice of reaching out to someone you don't know with a business proposal or introduction. Think of it as the digital version of a cold call, but way less intrusive. When done right, it’s a powerful way to generate leads, build partnerships, and grow your business. But here’s the catch: while cold emailing is perfectly legal, you have to follow a specific set of rules. This isn't just about checking a box; it's about protecting your business and ensuring your messages actually land in the inbox.

Ignoring compliance is like building a house on a shaky foundation—it’s only a matter of time before things start to crumble. These regulations, like the CAN-SPAM Act in the U.S. and GDPR in Europe, are designed to protect consumers from spam and deceptive practices. Following them isn't just a legal requirement; it's a sign of respect for your recipients. It shows you're a legitimate business, not a spammer, which is the first step in building trust. A solid outreach strategy is always built on a foundation of compliance, ensuring your efforts are sustainable and effective for the long haul.

The Real Risks of Ignoring the Rules

Let's be direct: not following the rules can have serious consequences. We're talking about hefty fines, potential lawsuits, and significant damage to your brand's reputation. For example, under the CAN-SPAM Act, fines can reach up to $53,088 for each email that violates the rules. That number alone should get your attention. Beyond the financial hit, getting labeled as a spammer can get your domain blacklisted by internet service providers, which means your emails—even the important, non-marketing ones—won't get delivered. If you're emailing people in specific regions, like California, you also have to respect their data rights, adding another layer of responsibility.

How Compliance Protects Your Reputation and Deliverability

On the flip side, think of compliance as your best defense and a powerful tool for success. When you follow the rules, you're not just avoiding legal trouble; you're actively building trust with the people you're emailing. A compliant email—one that’s honest, provides an easy way to opt-out, and clearly identifies you—shows that you value your recipient's time and privacy. This professionalism directly impacts your email deliverability. Mailbox providers like Gmail and Outlook favor senders who play by the rules, making it more likely your messages will land in the primary inbox instead of the spam folder. In short, compliance is the bedrock of a reputable and effective cold email program.

The Major Email Laws You Need to Know

Let's talk about the legal side of email. I know, the thought of regulations and acronyms can make your eyes glaze over, but sticking to the rules is non-negotiable for running a successful and sustainable outreach program. Getting this right protects your business, builds trust with your contacts, and is essential for maintaining high email deliverability. Think of these laws not as roadblocks, but as the guardrails that keep your strategy on track.

We're going to walk through the four major regulations you'll encounter most often: CAN-SPAM in the U.S., GDPR in Europe, CASL in Canada, and CCPA in California. Understanding the basics of each will give you the confidence to build campaigns that are both effective and compliant, no matter where your contacts are located.

CAN-SPAM Act (United States)

If you're emailing anyone in the United States, the CAN-SPAM Act is your rulebook. It’s less about preventing you from sending cold emails and more about ensuring you do it honestly. The law requires you to be upfront about who you are, include your valid physical mailing address in every email, and provide a simple, clear way for people to opt out of future messages. Don't take these rules lightly—the penalties for non-compliance can be steep, reaching over $50,000 for a single email that breaks the rules. It’s a straightforward set of guidelines that prioritizes transparency for the recipient.

GDPR (European Union)

Sending emails to contacts in the European Union means you need to be familiar with the General Data Protection Regulation (GDPR). This regulation is all about protecting personal data. For cold outreach, this means you must have a lawful basis, like a "legitimate interest," to contact someone. You also have to be transparent about how you collect and use their data and, just like with CAN-SPAM, provide an easy way to unsubscribe. The stakes are incredibly high with GDPR; fines for violations can reach up to €20 million or 4% of your company's global revenue, whichever is higher. It’s a serious law that puts individual data rights first.

CASL (Canada)

Canada's Anti-Spam Legislation, or CASL, is known for being one of the strictest email laws out there. Unlike CAN-SPAM, CASL generally requires you to have consent before sending a commercial email. This consent can be explicit (they signed up for your list) or implied (you have an existing business relationship, for example). Every message must clearly identify you as the sender and include a working unsubscribe mechanism. The penalties are significant, with fines for businesses reaching as high as $10 million. If you have Canadian contacts on your list, understanding CASL is absolutely essential.

CCPA (California)

Even if you're not based in California, the California Consumer Privacy Act (CCPA) likely affects you if you have contacts who live there. This law gives California residents more control over their personal information. A key part of the CCPA is the right for consumers to know what data is being collected about them and to opt out of their data being sold. For your email process, this means you need a clear system for handling these requests. Failing to comply can result in fines of $2,500 for unintentional violations and up to $7,500 for intentional ones.

Breaking Down the CAN-SPAM Act

If you’re sending cold emails in the U.S., the CAN-SPAM Act is your rulebook. Don’t let the official-sounding name intimidate you; its guidelines are mostly common sense. The law sets the rules for all commercial email, which includes the B2B messages you send to generate leads. It’s not just about blocking junk mail—it’s about creating a standard for legitimate commercial outreach.

Following these rules isn’t just about avoiding fines. It’s about protecting your sender reputation and ensuring your emails actually land in the inbox. Think of it as the foundation for a successful and sustainable cold email strategy. When you’re transparent and respectful, you build trust from the very first message.

Clearly Identify Who You Are

Transparency is non-negotiable. The CAN-SPAM Act requires you to clearly say who you are in every email you send. This means your "From," "To," and "Reply-To" fields must accurately identify you or your business. Hiding behind a vague or misleading sender name is a fast track to the spam folder and can damage your domain’s reputation.

Your recipients should know who is contacting them at a glance. Use your real name and the name of your company. This simple step builds immediate trust and shows you’re a legitimate professional, not a faceless spammer. It also ensures that if someone wants to reply, their message will get to the right place. It’s a basic sign of respect that also happens to be the law.

Write Honest Subject Lines

Your subject line is your first impression, and it needs to be an honest one. Under CAN-SPAM, your email subject lines shouldn't be misleading. They must accurately reflect the content of your message. This means no clickbait-y tricks or deceptive phrases designed to get an open at any cost. Using "Re:" or "Fwd:" to fake a prior conversation is a classic violation that email clients and recipients can spot a mile away.

Instead, focus on writing clear, relevant, and compelling subject lines that speak to your prospect's needs. A great subject line creates curiosity about what’s inside without making false promises. Honesty here not only keeps you compliant but also helps you connect with the right prospects who are genuinely interested in what you have to offer.

Offer a Clear Way to Opt-Out

Every email you send must give recipients a clear and obvious way to stop receiving messages from you in the future. The law states that you must include a way for people to stop getting emails from you, which is almost always an unsubscribe link in the email’s footer. Hiding this link in tiny font or using confusing language is a major compliance misstep.

Once someone opts out, you have to honor their request promptly—within 10 business days, to be exact. A solid email infrastructure makes managing these requests simple. Think of unsubscribes as a good thing; they help you clean your list so you can focus your energy on prospects who are actually interested. It’s a win-win for both you and your recipients.

Include Your Physical Address

To prove you’re a legitimate business, CAN-SPAM requires that you need to include a valid physical mailing address in your emails. This adds a layer of accountability and shows recipients that there’s a real company behind the message. This doesn’t have to be your home or main office; a registered P.O. box or a private mailbox from a service like UPS works perfectly well.

This information is typically placed in the footer of your email, right alongside your unsubscribe link. It’s a small detail that makes a big difference in terms of compliance and professionalism. According to the Federal Trade Commission, this requirement is a core component of the law, so it’s one you definitely don’t want to overlook.

Sending to Europe? What GDPR Means for Your Outreach

If your outreach campaigns include contacts in the European Union, you need to get familiar with the General Data Protection Regulation (GDPR). This isn't just a suggestion; it's a legal requirement that has a major impact on how you can conduct cold email. The rules apply whether your business is based in Paris, Texas, or Paris, France. If you’re processing the personal data of anyone in the EU, you’re on the hook for compliance.

Don't let the acronym scare you. At its core, GDPR is about transparency, fairness, and accountability. It ensures that you treat people's personal information with respect. For cold email, this means you can't just email someone out of the blue without a valid justification. You need to have a lawful reason for contacting them, be upfront about who you are, and make it easy for them to say "no thanks." Following these principles not only keeps you compliant but also helps build trust with potential customers from the very first touchpoint.

Have a Lawful Reason to Process Data

Under GDPR, you can’t collect or use someone's personal data—including their business email address—without a valid justification. This is what the regulation calls a “lawful basis for processing.” For cold outreach, you generally won't have someone's direct permission, so you'll need to rely on another lawful basis.

The most common one for B2B cold email is "legitimate interest." This means you have a valid business reason for contacting the person that is not outweighed by their individual rights to privacy. Before you even think about hitting send, you should be able to clearly articulate why your outreach is relevant and necessary for that specific contact. Documenting this reasoning is a key step in building a GDPR-compliant process.

Know the Difference: Consent vs. Legitimate Interest

It’s easy to confuse the rules for email marketing with those for cold email. Email marketing to a list of subscribers relies on consent—people have actively opted in to hear from you. Cold email is different. You’re contacting someone for the first time, so you don’t have their prior consent. Instead, you’ll likely rely on legitimate interest.

To use legitimate interest as your lawful basis, you need to perform a simple three-part check known as a Legitimate Interests Assessment (LIA). First, identify your purpose: What is your legitimate business interest? Second, prove necessity: Is this outreach necessary to achieve that purpose? And third, conduct a balancing test: Do your interests override the person’s rights and freedoms? For B2B outreach, a targeted, relevant email is more likely to pass this test than a generic blast to a random list.

Respect Your Contacts' Data Rights

GDPR gives individuals significant control over their personal data, and you have a responsibility to honor those rights. Your first email must be transparent. You should clearly state who you are and provide a simple explanation for why you’re contacting them. This is also where you must offer a clear and straightforward way to opt out of future communications. An unsubscribe link is non-negotiable.

Beyond the right to opt-out, people also have the right to access the data you hold on them, correct it, or have it deleted entirely. While you don't need to list all of these rights in every email, you must have a process in place to handle these requests promptly if you receive one. Being prepared to manage these requests shows respect for your contacts and is a fundamental part of GDPR compliance.

Handle International Data Transfers with Care

The internet has no borders, but data protection laws certainly do. A common mistake is thinking GDPR doesn't apply to businesses outside the EU. However, the regulation has what’s called "extraterritorial scope." This means the rules protect EU residents no matter where the company contacting them is located. If you're a US-based company sending emails to prospects in Germany, France, or any other EU country, you must comply with GDPR for those contacts.

Because of this, you can't treat your entire email list the same way. The best practice is to either segment your lists by geography and apply the appropriate rules for each region or simply adopt GDPR's high standards for all your outreach. The latter approach is often simpler and ensures you’re following some of the strictest, most respected data privacy principles across the board.

Costly (and Common) Compliance Mistakes to Avoid

Getting cold email compliance right can feel like a lot, but it often comes down to avoiding a few key mistakes. These aren't obscure technicalities; they're common slip-ups that can land your emails in the spam folder and your company in hot water. Think of compliance as the foundation of a successful outreach strategy. When you get it right, you not only protect your business but also build a better reputation with both inbox providers and potential customers. A solid email infrastructure can help with the technical side, but understanding the human element of compliance is just as important.

Ignoring these rules doesn't just risk fines; it directly impacts your ability to reach the inbox. Internet Service Providers (ISPs) and email clients are getting smarter about filtering out messages that look unprofessional or untrustworthy. Simple mistakes, like a missing unsubscribe link or a deceptive subject line, are huge red flags that can tank your sender reputation. Once that reputation is damaged, it's incredibly difficult to repair, and all your future campaigns will suffer. Let’s walk through the most frequent errors so you can build a process that keeps your outreach effective and above board.

Forgetting the Unsubscribe Link

This is one of the most critical and easily avoidable mistakes. Every commercial email you send must give recipients a clear and simple way to opt out of future messages. As compliance guides emphasize, "[y]ou must include a way for people to stop getting emails from you." This isn't just a suggestion; it's a legal requirement under laws like the CAN-SPAM Act.

Making the unsubscribe process difficult or hiding the link in tiny font is a fast track to getting marked as spam. When people can't easily opt out, they'll hit the spam button instead, which damages your sender reputation. A visible unsubscribe link shows respect for the recipient's inbox and is a sign of a professional, legitimate operation. It helps keep your list healthy by removing people who aren't interested, which ultimately improves your campaign performance.

Using Misleading Subject Lines

Your subject line is your first impression, and it needs to be an honest one. While it’s tempting to write something clever to grab attention, you have to make sure it accurately reflects the email's content. Deceptive subject lines are a direct violation of compliance rules, which clearly state that "[y]our email subject lines shouldn't be misleading." This means avoiding things like adding "Re:" or "Fwd:" to imply a previous conversation that never happened.

Instead of relying on tricks, focus on writing a subject line that is clear, relevant, and provides a compelling reason for the recipient to open your message. A straightforward subject line like "Idea for improving your content workflow" is much better than a vague or deceptive one. Honesty builds trust from the start and sets a professional tone for your entire interaction.

Failing to Identify Yourself Properly

Transparency is essential in cold outreach. Your recipients have a right to know who is contacting them. From the moment they open your email, "[y]ou must clearly say who you are." This means your "From" name should be recognizable, and the body of your email should clearly state your name and the company you represent. Hiding your identity is a major red flag for spam filters and immediately creates suspicion.

Beyond just your name, the CAN-SPAM Act also requires you to include a valid physical postal address in every email. This could be your current street address, a post office box you’ve registered, or a private mailbox. Including this information shows that you're a legitimate business with a real-world presence, which helps build credibility and ensures you meet legal standards.

Mishandling Contact Data

In an age of heightened data privacy awareness, how you handle contact information matters more than ever. A core principle of regulations like GDPR is data minimization. You should "[o]nly gather the minimum amount of personal data you need (like just an email address and name)," as outlined in this GDPR-compliant cold email guide. If you don't need a prospect's phone number or job title for your initial outreach, don't collect or store it.

Collecting excessive data not only violates privacy principles but also increases your liability. The more information you hold, the greater the risk if a data breach occurs. Stick to the essentials and ensure you have a lawful basis for processing the data you do have. This approach shows respect for your contacts' privacy and helps you maintain a focused, compliant, and secure database for your outreach campaigns.

Believing Common Myths About Cold Email

One of the most persistent myths is that all cold email is illegal spam. This simply isn't true. As compliance experts often clarify, "[c]old emailing is legal, but you must follow specific rules to avoid big fines and protect your company's good name." The distinction between legitimate outreach and spam comes down to following the guidelines set out in the key legislation you must know.

Other common misconceptions include believing that B2B emails are exempt from the rules or that the regulations don't apply to small businesses. In reality, the law applies to all commercial messages. Understanding the facts and building a compliant process is what separates professional marketers from spammers. When you commit to ethical outreach, you can confidently use cold email as a powerful tool for growth.

How to Build a Compliant Cold Email Process

Knowing the rules is one thing, but putting them into practice is what keeps you safe. Building a repeatable, compliant process isn't just about avoiding fines; it's about creating a sustainable outreach engine that protects your sender reputation and gets results. A solid process removes the guesswork and ensures everyone on your team follows the same best practices, every single time. It turns compliance from a stressful afterthought into a simple, check-the-box part of your workflow.

Think of it as the foundation of your entire cold email strategy. Without it, even the most brilliantly written campaigns can crumble under the weight of deliverability issues and legal risks. Here’s how you can build a process that works.

Keep Your Email Lists Clean and Verified

Sending emails to invalid or outdated addresses is a surefire way to damage your sender reputation. High bounce rates signal to email providers that you aren't managing your lists properly, which can land your messages in the spam folder. To avoid this, you need to practice good data hygiene. Before you even think about hitting send, run your contact lists through an email verification service to scrub out invalid addresses. Make this a regular habit. As experts suggest, you should review your contact lists quarterly to remove bounced addresses and update any outdated records. This simple step keeps your lists healthy and your deliverability strong.

Create a System to Manage Opt-Outs

Every cold email you send must include a clear and easy way for recipients to opt out, as required by laws like the CAN-SPAM Act and GDPR. But having an unsubscribe link is only half the battle. You also need a bulletproof system for honoring those requests promptly. When someone opts out, their address should be immediately added to a suppression list that prevents them from receiving any future emails from you. This process should be automated. Manually managing opt-outs is a recipe for human error, which can lead to costly compliance violations and frustrated recipients.

Maintain Clear and Accurate Records

If a recipient or a regulatory body ever questions your outreach, you need to be able to explain where you got their information and why you contacted them. This is especially crucial for GDPR compliance, which requires you to have a lawful basis for processing data. For B2B cold email, this is typically "legitimate interest." To prove it, document your data sources, the date you acquired the contact information, and your reasoning for believing your offer would be relevant to them. A simple way to do this is to include a brief, clear statement in your email templates explaining how you processed their data and their right to object.

Schedule Regular Compliance Check-ins

Email laws and best practices can change, so compliance isn't a "set it and forget it" task. To stay on top of things, schedule regular compliance check-ins with your team—monthly or quarterly is a good cadence. Use this time to review your email templates, data collection methods, and unsubscribe process. Check for any updates to major regulations like CAN-SPAM or GDPR. These check-ins ensure your process remains effective and that your team stays educated on the latest requirements, preventing bad habits from creeping into your workflow.

The Right Tools to Keep Your Outreach Compliant

Knowing the rules is one thing, but consistently applying them is another. The right technology is your first line of defense for maintaining compliance and protecting your sender reputation. A solid tech stack automates the tedious parts of compliance, freeing you to focus on writing great emails. From verifying contact lists to authenticating your domain, these tools work in the background to keep your outreach effective.

Key Features in Compliance Software

Your email platform should make compliance simple. Look for a robust system for managing unsubscribes, ensuring anyone who opts out is immediately removed from all campaigns. It should also support list hygiene by helping you remove invalid or unengaged email addresses. To follow anti-spam laws, your tools should also allow for personalization. This shows you’re sending a considered message, not a generic blast, and helps you manage your data responsibly.

Set Up Email Authentication (SPF, DKIM, DMARC)

Think of email authentication as your digital passport. It proves to ISPs like Google and Microsoft that you are who you say you are. Setting up these records is a non-negotiable step. SPF, DKIM, and DMARC work together to verify your identity and protect your messages from being altered. Properly configured authentication is a powerful signal that you’re a legitimate sender, which is crucial for improving your email deliverability.

The Benefits of a Dedicated Email Infrastructure

Using a shared email service is like living in an apartment building—if your neighbor causes trouble, everyone can face consequences. If another user on a shared IP sends spam, your emails can get blocked. A dedicated email infrastructure gives you your own private address, so your sender reputation is entirely in your hands. This control is essential for high-volume outreach and ensures your compliance directly impacts deliverability. With a custom-built system, you can maintain a pristine reputation.

Use Automation to Monitor for Issues

Compliance isn’t a one-time setup; it’s an ongoing process. Automation is your best friend here. Set up workflows to automatically handle unsubscribe requests the moment they come in, honoring every opt-out without delay. You should also automate monitoring for key email metrics like bounce rates and spam complaints. These are early warning signs that something is wrong. Using automation to stay proactive helps you catch compliance issues before they damage your domain reputation.

How to Stay Compliant Across Borders

Sending emails internationally means you’re not just crossing time zones; you’re crossing legal jurisdictions. What’s perfectly acceptable in one country could land you in hot water in another. Managing compliance across borders can feel like a huge task, but it’s entirely manageable with the right approach. It’s not about becoming a lawyer overnight. It’s about building a process that respects international rules and protects your business.

Think of it as your global passport for outreach. A solid, internationally-aware compliance strategy ensures your messages are welcomed, not blocked, and keeps your sender reputation strong no matter where your contacts are located. By understanding the landscape and putting a few key practices in place, you can confidently connect with leads around the world.

Juggling Rules from Different Regions

If you’re emailing contacts in different parts of the world, you need to be aware of the local laws governing commercial emails. For instance, the United States has the CAN-SPAM Act, while Europe operates under the much stricter GDPR. Canada has its own anti-spam legislation (CASL), and even states like California have specific privacy laws like the CCPA.

Understanding the nuances of each regulation is the first step. You don't need to memorize every clause, but you should know the core requirements for the regions you target. For example, GDPR requires a clear legal basis for processing someone's data, while CAN-SPAM is more focused on the content of your email and opt-out mechanisms. A great starting point is to familiarize yourself with the key legislation for cold email in your primary markets.

Train Your Team on Best Practices

Compliance isn’t a one-person job; it’s a team sport. Everyone involved in your outreach—from list building to campaign management—needs to be on the same page. A single mistake from a well-meaning team member can put your entire operation at risk. That’s why ongoing training is so important.

Your team should be educated on the basics of major anti-spam laws and data protection principles. Make sure they understand the importance of only using properly sourced data, respecting privacy, and handling opt-out requests promptly and professionally. When your whole team understands the "why" behind the rules, they become your best defense against compliance issues. This shared knowledge builds a culture of responsibility that protects your brand.

Stay Current on Regulatory Updates

Data privacy and email marketing laws are not set in stone. They evolve as technology and consumer expectations change. A strategy that was compliant last year might need adjustments today. Staying informed about regulatory updates is a critical part of a long-term compliance strategy. This is especially true for regulations like GDPR, which continues to be interpreted and refined.

Make it a habit to follow reputable industry blogs or legal tech news sites that cover data privacy. For example, understanding how to maintain a GDPR-compliant cold email strategy requires staying on top of best practices for data sourcing and protection. Scheduling a quarterly review of your processes against any new legal updates can save you from falling out of compliance without even realizing it.

Document Your Processes and Manage Consent

If you ever face a compliance audit, you’ll need to be able to show your work. That’s where documentation comes in. Under regulations like GDPR, you must have a valid reason, or "legal basis," for collecting and using personal data. You need to document these reasons clearly.

Create an internal guide that outlines your entire process: where you source your data, how you verify it, what your legal basis is for contacting individuals, and how you handle unsubscribe requests. This documentation is your proof of due diligence. A clear, GDPR-compliant cold email guide can help you structure your own internal processes for managing consent and documenting your outreach activities, ensuring you’re always prepared to demonstrate your commitment to compliance.

Frequently Asked Questions

Is sending a cold email even legal? Yes, it absolutely is. The key distinction is between legitimate, professional outreach and spam. Laws like the CAN-SPAM Act in the U.S. don't outlaw cold email; they set clear rules for how to do it respectfully and transparently. As long as you are honest about who you are, provide a clear way to opt-out, and have a legitimate business reason for your message, you are engaging in a perfectly legal and effective business practice.

What's the biggest difference between the US (CAN-SPAM) and EU (GDPR) rules? The main difference comes down to the initial justification for contact. In the U.S., the CAN-SPAM Act focuses more on giving recipients the right to opt-out of emails. In the EU, GDPR is stricter upfront, requiring you to have a "lawful basis," like a documented legitimate interest, before you even process someone's data or send that first email. Think of it this way: CAN-SPAM is about the right to say "stop," while GDPR is about having a good reason to say "hello" in the first place.

Do I really need to include my physical address in every email? You do. This is a non-negotiable requirement of the CAN-SPAM Act. Including a valid physical mailing address is seen as a sign of a legitimate business, proving there's a real company behind the email. It doesn't have to be your main office; a registered P.O. box or a private mailbox from a commercial service works just as well and satisfies the legal requirement.

What's the fastest way to get my emails marked as spam? The quickest way to land in the spam folder is by making it difficult for people to unsubscribe. If someone can't easily find an opt-out link, their next click will be the "report spam" button. This sends a powerful negative signal to email providers and damages your sender reputation. Other fast tracks to the spam folder include using deceptive subject lines or failing to clearly identify who you are.

If someone unsubscribes, should I just delete them from my list? It's actually better to add them to a suppression list rather than deleting them completely. A suppression list is a permanent record of people who have opted out. This ensures you don't accidentally re-add their contact information to a new list and email them again in the future. It's the most reliable way to honor their request and maintain a clean, compliant outreach process.