Best Email Marketing Practices for 2025

We have gathered information from top cold emailers worldwide and condensed the common elements found in successful cold email campaigns into a checklist. We have divided it into two sections: copywriting and technical. Let’s dive in:

Cold Email Copywriting Checklist

1. Avoid using images: It’s best to refrain from including images in your initial email. Keep the first email concise with fewer than 150 words, as a low word-to-image ratio can trigger spam filters. Moreover, self-hosted images from poorly rated domains may activate spam filters.

2. Limit the number of links: Spam filters tend to be sensitive to links, even if they are masked as redirects. Try to include only one link (your own) and avoid adding multiple links. Having multiple links can dilute the Call to Action (CTA) and confuse the reader, detracting from the primary focus.
3. Keep emails brief: People prefer reading concise and straightforward messages rather than long walls of text. Introduce yourself, provide relevant social proof, and mention how quickly users can achieve a desired outcome by engaging with you. Use short paragraphs, keeping them to a maximum of two sentences each.
4. Avoid repeating the same email in follow-ups: If the recipient didn’t respond to your initial message, it’s unlikely they will engage with the same content again. Instead, rephrase your pitch and tailor it specifically to the user. This approach also improves deliverability, as repetitive content can trigger spam filters.
5. Maintain a grade 5 reading level: Keep your language simple, avoid complex phrases, and eliminate jargon. Research shows that 6 out of 10 users disengage after encountering a single word they don’t understand. User grade level reading testers.
6. Avoid spam-triggering keywords: Starting a cold email with words like “SALE!” or using subject lines in all caps can raise red flags for spam filters. While the goal is still to sell, it’s essential to strike a balance and not sound like a dubious source. Always use subject line testers.
7. Don’t push for a sale in the first email; aim for a meeting instead: A common mistake beginners make is asking for a purchase and providing a link to buy right away. Instead, the primary purpose of the first email should be to initiate a conversation or request a demo. Demos are better suited for driving a deal. Cold emails should resemble conversations rather than sales pitches. Imagine reading your email out loud; if it doesn’t sound like something you’d say to a stranger on the street or at a networking event, make the necessary changes before hitting send.
8. Avoid HTML-heavy emails: Cold emails should appear personalized, as though you wrote them specifically for the recipient. While tools like smartwriter.ai can assist with personalized scaling, avoid sending templated emails with images and flashy buttons. HTML templates are better suited for subscriptions and newsletters, not cold outreach.

Cold Email Technical Checklist

1. Use complementary domains: To protect your email sending reputation, avoid using your primary domain for cold emails. If your company email is vin@vin.com, for example, don’t send emails from addresses like van@vin.com Purchase additional domains that complement your primary one (preferably .net/org). For instance, you can acquire domains such as viney.com or vini.com or something reflecting your domain. Redirect these domains to your primary domain in the DNS settings. This redirection ensures that if someone tries to visit the complementary domains, they end up on your primary domain.
2. Avoid using alias accounts: Alias accounts do not function as separate email accounts; they are merely masked addresses associated with your main account and do not maintain separate reputations.
3. Use spintax for improved deliverability: Sending thousands of emails with identical content may raise suspicion with email software and potentially trigger spam flags. Spintax provides a solution by allowing you to create variations of your copy using synonyms. This makes each email slightly different and enhances deliverability. For instance; {Hi|Hello|Hey|What’s up}. This generates four distinct emails, each with slightly different content. It improves deliverability and allows you to analyze which verbiage yields better results.

4. Test different copies for deliverability and experimentation: Similar to spintax, you can A/B test different versions of your copy by changing entire sections of the email. This approach helps improve deliverability by introducing variation and provides an opportunity to assess which messaging generates better return on investment (ROI).
5. Set up DKIM, DMARC, MX and SPF: These security protocols assist email accounts in verifying the authenticity of the sender, preventing spoofing. These protocols enhance deliverability and avoid being flagged as spam.
6. Build reputation of your domains: Domain warm-up/reputation-building procedures protect your emails from being marked as spam and build your sender reputation. Use a system that mimics human-like sending behavior, consistently improving your reputation and increasing the chances of your emails landing in recipients’ inboxes rather than their spam folders.
7. Limit daily email sending to fewer than 100 emails per account: Excessive email volume can harm your email reputation, especially for domains less than a year old. As your domain ages, you can gradually increase the number of emails sent per day.
8. Randomize email sending: Whether you’re using email software or sending emails manually, avoid sending them in bursts. Introduce natural gaps and randomization in your sending schedule to emulate human behavior. This approach helps bypass spam filters and prevents triggering automation flags.
9. Gradually increase email volume: When starting the warm-up process, don’t immediately send a high volume of emails. Allow the email account to acclimate to the IP network and adjust to sending emails. Sending 100 emails on the first day with a fresh domain is not advisable. Instead, gradually increase the volume, such as sending five emails per day until reaching a steady rate.
10. Use unsubscribe texts instead of links: While including an unsubscribe link is necessary for GDPR compliance, you can also request that leads respond with a specific text if they’re not interested. For instance, you can add a line at the bottom of your email that says, “Please respond with ‘not interested’ if this isn’t for you.” This approach increases your reply percentage and improves deliverability. Additionally, you can easily exclude non-responsive recipients using rules in your cold emailing tool.
11. Set up custom domain tracking: Tracking clicks and open rates requires injecting a small snippet of HTML into your email. While this is standard practice and provides valuable analytics, it can sometimes impact campaign deliverability. Email service providers are aware that multiple campaigns from different users all send requests to the same tracking URL, potentially leading to a decline in deliverability. To address this, you can “mask” the tracking URL with your own domain.
12. Maintain a time gap of at least 5 minutes between emails: Configure your email sending schedule to include a gap of at least 5 minutes between emails. This practice helps maintain your email reputation and prevents triggering automation flags.
13. Set up a Do Not Contact (DNC) list: Maintaining a DNC list ensures you don’t send messages to individuals who have explicitly asked not to be contacted or whose emails have previously bounced. Including a DNC list protects your email reputation and reduces the chances of future emails being marked as spam due to high bounce or spam-flag rates.
14. Avoid personal emails to prevent spam traps: Send emails to business email addresses (e.g., vini@companyname.com) rather than personal email accounts like vini@gmail.com. Personal Gmail accounts typically have more aggressive spam filters, and promotional folders are more strictly regulated. By sending emails to company accounts, you increase the likelihood of landing in the recipient’s primary inbox.
15. Implement inbox rotation: When reaching out to a large number of leads, it’s not sustainable to send all emails from a single account. Instead, you can distribute your leads across multiple email accounts with different domains. For example, if you have 20 email accounts, each sending 50 emails, you can reach 1,000 leads in a single day without jeopardizing your reputation. To simplify the management of these campaigns use a unified inbox.

By following these guidelines, you can optimize your cold email campaigns while minimizing the risk of triggering spam filters or facing other deliverability issues