How to warm up domains and boost cold email replies

TL;DR

Deliverability is the key to inbox placement and must come before copy. Start with a proper warm up of a separate sender domain, then craft openable subject lines and human first lines. Use short, low friction follow-ups to maximize replies, since 58% come from the first email and the rest come from a four to seven touch sequence.

Transcript

The average cold email gets a reply about 3% of the time. So, you send 100, 97 people ignore you, and the sender blames the inbox or the algorithm, but not the tool. So, over the last stretch, I went deep on cold email, the campaigns that print booked calls, and the ones that die on arrival, and I kept the receipts. The gap between them comes down ... Read More

Key Insights

• Deliverability is the share of emails that reach the actual inbox, not just the sent folder, and it hinges on the sender domain reputation.
• Warm-up means gradually increasing sending from a separate domain over 4 to 6 weeks while keeping bounce rate under 2 percent.
• A good subject line should be opened, not impressive, with short lowercase phrases that feel like they come from a coworker.
• First-line relevance matters more than generic personalization; reference a specific problem the recipient actually has.
• Emails should be written as if texting one person, with plain language and contractions to feel human.
• The primary goal of the first email is to generate a reply, not to close a deal or schedule a call.
• Follow-ups account for a large portion of replies; a four to seven touch cadence performs best, with each follow-up offering a new angle.
• The messaging system can be managed within a platform like Instantly, which handles warm-up, sending, and follow-up sequencing.
• More videos from this channel:
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  • How to start cold emailing to book calls and make money
• More from this channel: Instantly

Questions & Answers

Q: How does deliverability affect cold email campaigns

Deliverability determines whether emails land in the recipient's actual inbox rather than being filtered or ignored. A fresh domain sent in high volume can be flagged as spam, harming future outreach. Proper warm-up builds a positive sender reputation over weeks, ensuring subsequent campaigns have a higher chance of being seen and replied to.

Q: What is the recommended warm-up process for a new sending domain

The recommended warm-up process starts with a small volume, around 5 to 10 emails per day, and gradually increases over 4 to 6 weeks. The goal is to keep the bounce rate under 2 percent while the domain earns trust with inbox providers, avoiding sudden spikes that trigger spam flags.

Q: Why is the subject line described as vital in cold emails

The subject line's job is to get the email opened. Personalization and relevance improve open rates; shorter, lower-case phrases that feel like they came from a coworker outperform generic, salesy lines. A good subject line reduces walls and increases the chance the recipient will read the body.

Q: What should the first line of a cold email accomplish

The first line should reference something specific and true about the recipient and connect it to a real problem they might have. Avoid generic openings about the sender; relevance and specificity engage the reader and reduce the likelihood of deletion, increasing the chance they read the rest of the email.

Q: What is the main function of the first cold email, according to the video

The main function is to elicit a reply, not to close a sale. A low-friction ask, such as a small, easy yes or a quick value proposition, lowers the barrier for a reply. Frictionless engagement helps move the conversation toward a potential next step.

Q: How many total touches are recommended in a cold email sequence

The recommended cadence is around four to seven touches. Fewer than four may miss replies, and more than seven can annoy recipients and harm deliverability. Each follow-up should offer a new angle or value, not just a reminder that you exist.

Q: What role does follow-up play in reply rates

Follow-ups contribute to a substantial share of replies, with about 42 percent coming from the follow-up sequence. Each follow-up must present new value or a fresh angle rather than a simple reminder, to keep the recipient engaged and inclined to respond.

Q: How can a tool like Instantly assist with cold email campaigns

A tool like Instantly streamlines the process by providing done-for-you domain setup, warm-up, and inbox rotation. It helps manage sending accounts, tracks health scores, and executes the four-to-seven touch cadence, enabling marketers to focus on message quality while maintaining deliverability and workflow efficiency.

Summary & Key Takeaways

• A primer on cold email fundamentals: deliverability determines whether emails reach the inbox, not just content or design, and warm-up is essential to avoid flagging a new domain.

• The video emphasizes writing like a real person, using specific observable problems in the first line, and keeping the body plain language to improve reply rates.

• A practical workflow is shown for setting up a separate sending domain, warming it up over weeks, and building a cadence of four to seven follow-ups to maximize replies.