To ensure that your emails actually arrive in your inbox (and not in spam), it's essential to configure your DNS settings. This small technical adjustment has a big impact on your deliverability, your domain reputation and the performance of your sequences.

Don't worry, we'll take you through it step by step: see our DNS configuration guide in the Help Center. Once your SPF, DKIM and DMARC records are in place, you can send your campaigns with complete peace of mind.

Check settings in Zeliq or use sites like https://mxtoolbox.com/DnsLookup.aspx to "spot problems" with your current setup and help you resolve them.

Set up a dedicated domain for your cold emailing campaigns. Protect the reputation of your primary domain and improve your deliverability by using a secondary domain (like entreprise.io).

Check that your email authentication settings are correctly configured. Validate SPF, DKIM and DMARC records to prove the legitimacy of your emails. Use tools like MXToolbox or Mail-tester to check your settings and improve deliverability.

Set up a redirection from your dedicated sending domain to your main website. When your prospects check your domain, they arrive on your real site. This simple step adds credibility and shows that you're a real company.

Send your emails from a personalized email address, not a no-reply address. Use personalized addresses like [email protected] to build trust and encourage responses .

Contact only verified email addresses. Use email verification tools to confirm that addresses are valid and active before sending. This protects your reputation as a sender and reduces bounce rates, which are detrimental to your deliverability.

Build your sender reputation gradually. Start with a maximum of 10 emails per day, then increase slowly over time. This warm-up period proves to e-mail providers that you're a trusted sender, not a spammer. Patience pays off.

Increase your volume slowly and safely. Increase your number of daily emails by 20% every 2-3 days. This constant progression builds your reputation as a sender without triggering spam filters.

Stay below 50 emails per day for your first two weeks. This warm-up phase is essential to build your sender reputation without raising any red flags.

Even once your domain is warmed up, don't exceed 50-60 emails per day. This volume is the sweet spot for maintaining excellent deliverability. Beyond this, spam filters become more aggressive and your reputation degrades

Send your e-mails from a personalized e-mail address, not a no-reply address. Use personalized addresses like [email protected] to build trust and encourage responses .

Avoid sending all your emails at the same time each day. Vary times and days to simulate natural, human sending behavior. Bulk sends at exactly 9:00 AM look like automation.

Limit your emails to 4-5 lines maximum. Short emails look like natural, human messages. Long emails (>10 lines) look like commercial newsletters and trigger spam filters. Less = more.

Remove all bullet points from your emails. Bullet points are a strong marker of automated commercial content. Conversational emails between colleagues never use bullet points. Plain text format only.

Avoid emojis in your message body. One emoji in the subject might be okay, but multiple emojis in the content signal a marketing email and trigger filters. Stay professional and clean.

Use plain text format without complex HTML formatting. Avoid bold, italic, colors, or tables. These elements look like marketing emails and reduce your deliverability.

Absolutely avoid images in cold emails. Image-heavy emails trigger spam filters and slow loading. Focus on clean text messages for better deliverability and faster impact.

Keep your signature simple and clean. Drop the logos, images, and complex HTML formatting. A plain text signature with your name and email stays professional without triggering filters.

Write subjects that sound like emails between colleagues. Example: "Question about your offices" ✅ vs "Optimize your real estate!" ❌. Conversational subjects bypass filters and generate more opens.

Avoid CAPS in your subject line. They scream "SPAM" to filters and readers. Use normal case to stay professional and conversational.

Limit yourself to a single exclamation mark maximum. Multiple exclamation marks (!!!) are a classic spam signal. Stay sober and professional.

Avoid trigger words like "free," "urgent," "promo," "offer," "exclusive." These spam-trap terms send your emails straight to junk. Use natural, conversational language that provides value.

Focus on one problem or benefit per email. Don't list 6 different services. The goal of the first email is to get a response, not to sell everything. One clear proposition generates more replies.

End with an open-ended question that encourages response.

"Are you experiencing any issues with..." ✅ vs "Are you available for a call?" ❌.

Open questions generate 3x more responses than meeting requests.

Your call-to-action should be clear and simple. Stay light with simple, frictionless requests like "Are you open to a quick chat?" Actionable CTAs generate more responses than aggressive asks.

Use the {{firstName}} variable to personalize the beginning of your email. "Hi Sarah" creates an immediate connection. Personalization isn't just a best practice, it's often a legal requirement and a 1-to-1 signal for filters.

Integrate the company name ({{company}}) naturally into your message. "I saw that Acme Corp manages multiple sites..." shows you've done your research and this isn't a mass send.

Add a unique context element: their industry, location, recent news, or an intent signal. This deep personalization proves your email is truly 1-to-1, not a mass template.

Regularly remove invalid, non-existent, or bounced email addresses. These dead addresses damage your reputation with every send. Monthly cleaning maintains a healthy list.

If you receive "inbox full" bounces, retry 1-2 times a few days apart. If the problem persists, remove this contact. A constantly full inbox signals an inactive account.

Some corporate servers have extremely strict security rules and systematically reject cold emails. If you see recurring bounces from the same domain, adapt your approach or remove those contacts.

If you detect temporary server errors (4xx codes), wait before resending. A temporarily unavailable server doesn't mean invalid address. Retry after a few hours.

Target business contacts exclusively. B2B cold emailing has different legal requirements to B2C. Focus on business email addresses to stay compliant and reach decision-makers.

Always include an active unsubscribe link. It's a legal obligation and a signal of trust. Make it easy for those who aren't interested to unsubscribe. Respect builds reputation.

Some countries have strict opt-in requirements for cold email. Find out about regulations before sending to contacts in highly regulated regions to avoid legal problems and penalties.

Keep your bounce rate below 5%. A high bounce rate signals a poor-quality list and damages your reputation as a sender. Clean up your contact list regularly and check emails before sending to stay in the safe zone.

Aim for zero spam complaints. Even a few complaints can damage your deliverability and sender score. Focus on relevant, personalized prospecting, and always include an easy unsubscribe option to avoid complaints.

Aim for an open rate above 20%. This metric shows that your subject lines are working and that your emails are reaching the inbox. Test different approaches, personalize your messages and send at optimal times to increase opens.

Aim for a response rate of over 5%. This is the ultimate success metric: it means your message has aroused genuine interest. Write relevant, personalized emails with clear value propositions and simple CTAs to generate responses.

A burned domain = lost trust = weeks of recovery.

Focus on clean, consistent sending over volume. Always.