The cold email playbook

1The rules that decide if your email arrives

Gmail and Yahoo check who you are before they show your email. Both publish rules for anyone sending in volume. Break them and your email can bounce before a buyer sees a word.

• SPF: a DNS record that lists the servers allowed to send mail for your domain.
• DKIM: a signature that proves nobody changed the message on the way.
• DMARC: a policy that tells providers what to do when SPF or DKIM fails.
• Spam rate: Gmail and Yahoo cap it at 0.3% of mail reported as spam. Google recommends staying under 0.1%.

Google treats a domain sending about 5,000 or more messages a day to personal Gmail accounts as a bulk sender. Google counts all mail from the same domain together, so your whole team’s volume matters. Bulk senders need all 3 records, and since late 2025, mail that breaks the rules can draw a hard bounce.

Where you send from matters too. In Hunter’s 2026 data, cold email from a custom domain drew a 5.2% reply rate, against 2.5% from free webmail. Send from a mailbox on your company’s domain.

Track spam rate in Google Postmaster Tools and bounces in your sending tool. Instantly’s deliverability guide says to pause a mailbox once its bounce rate passes 2%.

Do this today: send a test to a personal Gmail account, open it and choose Show original. You want PASS next to SPF, DKIM and DMARC.

2Warm up a new domain and mailbox

A new domain or mailbox has no sending history, so providers hold back their trust. Warm up builds that history with small, real volume before your first campaign.

Do these steps in order. Move on only after a clean week: no spam complaints and bounces under 2%.

• Set up SPF, DKIM and DMARC before the mailbox sends anything.
• Finish the mailbox: your real name, a photo and a plain signature with your title.
• Start with real conversations. Email colleagues and partners who will open and reply.
• Turn on the warm up feature in your sending tool, if your team uses one, and leave it running.
• Add cold email in small batches, to verified addresses only.
• Raise volume a little each week, never in a jump.

If spam complaints or bounces rise, drop back a step. Bounces come from dead addresses, so verify every address before it enters a sequence.

Pushing volume too soon can damage the sending domain for your whole team. A mailbox your team has used for months may only need a weekly check of spam rate and bounces.

Do this today: ask your manager the age of your domain and whether your mailbox is already warm.

3Find a real signal for every prospect

A signal is a recent, public fact that gives you a reason to write today. Without one, your email reads like every other cold email in the inbox. Look in these places, in this order:

• Their careers page: new roles show where the team is growing.
• Their LinkedIn: posts, comments and job changes from the last month.
• Company news: launches, new markets, new leaders and funding.
• Reviews of their product: what users praise and complain about most.
• Your CRM: past conversations, lost deals and notes from your team.

Cap research at 5 minutes per prospect and set a timer. If nothing turns up, try a peer at the same company or move to the next name.

Write the signal in 1 line, then add why it matters to the buyer. That pair becomes your first line:

• Signal: SDR roles open in Mexico City. Why it matters: new reps need coaching before they book meetings.
• Signal: the head of support posted about slow ticket replies. Why it matters: slow replies put renewals at risk.
• Signal: a new VP of Sales started last month. Why it matters: new leaders review the tools they inherit.

Do this today: research your next 5 prospects with a timer running.

4Write the email in 4 parts

Keep the whole email short enough to read on a phone without scrolling. It has 4 parts, in this order:

• Subject: 2 to 4 plain words a colleague might write. No hype and no tricks.
• First line: the signal and why it matters, about the buyer before you.
• Problem: 1 problem people in their role face, in words they would use.
• Ask: 1 small question about interest, never a demand for a meeting.

Cut every line about your company that comes before the problem. The reader decides from the first line whether the email fits. Here are 3 full emails for 3 situations, labeled by part:

• Situation: a new VP of Sales who is hiring SDRs
• Subject: ramping the new SDRs
• First line: Hi Laura, congrats on the new role. I saw the SDR openings on your careers page.
• Problem: New SDRs often learn the pitch on live prospects, and good accounts pay the price. I help sales leaders run short practice calls, so reps sound ready before they dial.
• Ask: Worth a look before the new class starts?
• Sign off: Daniel

• Situation: a head of support who posted about slow replies
• Subject: your Monday backlog post
• First line: Hi Marcus, your post about the Monday ticket backlog stuck with me.
• Problem: When weekend tickets pile up, first replies slip and customers feel it on Monday. I help support teams answer routine tickets overnight, so Monday starts with a short queue.
• Ask: Want a 2 minute video of how it works?
• Sign off: Sofia

• Situation: a past prospect who went quiet, and now you have news
• Subject: month end approvals
• First line: Hi Priya, the accounting integration you were waiting for went live this month.
• Problem: In March you said month end approvals were slowing your close, and that missing link was the blocker.
• Ask: Is the close still slow, or did you solve it another way?
• Sign off: Andres

5Follow ups that add something new

A single email is easy to miss, so plan your follow ups before the first send. Each one must add 1 of these new things:

• A short customer story from their industry, told in 2 sentences.
• A useful resource: a guide, a checklist or a template they can use without a call.
• A new angle on the same problem, seen from another role on their team.
• A fresh signal: a new post, hire or launch since your last email.

Add the phone as well. In Gong Labs data, email reply rates rose from 2.73% to 5.87% when the rep also left a voicemail. A sample sequence to adjust:

• Day 1: the first email.
• Day 3: a call, plus a short voicemail naming your email subject.
• Day 6: follow up 1, a customer story.
• Day 10: follow up 2, a useful resource.
• Day 15: follow up 3, a short and polite close.

• Example: follow up 2, for Laura
• Subject: re: ramping the new SDRs
• What is new: Hi Laura, 1 more idea for the new class. I wrote up the first month practice plan sales leaders ask me for: daily call drills, a scorecard and a Friday review.
• Ask: Want a copy?
• Sign off: Daniel

Reply in the same thread so the history stays visible. If you cannot name what is new, skip the send, and stop the sequence when they answer.

6Read your reply rate and fix 1 thing

Reply rate is replies divided by emails delivered, per sequence. Instantly’s 2026 Cold Email Benchmark Report puts the average at 3.43%. Use the average as a reference point, never a volume target.

Below the average, work through these checks in order. Each one rules out a cause before you rewrite the copy.

• Bounce rate above 2%: a data problem. Pause the mailbox and verify the list.
• A record fails or tests land in spam: a setup problem. Fix the setup before you send more.
• Most replies say no thanks: a targeting problem. Compare the list with your best customers.
• Almost no replies: a subject or first line problem. Rewrite those 2 parts first.
• Replies but no meetings: an ask problem. Make the ask smaller.

Change 1 thing at a time. Send the new version to a similar list and compare the results with the old version.

Above the average? Look past reply rate to positive replies and meetings held. Those numbers show which signals and asks deserve more of your week.