Cold email has a reputation problem. Recipients call it spam, inboxes are full of AI-written messages that all sound alike, and Gmail and Outlook have tightened their rules for senders. Founders reasonably ask whether it is still worth doing at all.
The question appears regularly on Hacker News, usually with a request for real numbers and a setup that works. The replies split between people who still book meetings through cold email and people who report senders to blocklists.
Both groups are describing real behaviour. Cold email still works for B2B when it is small, specific and technically clean, and it fails as soon as it is treated as a volume game.
What the numbers say
The most current benchmark comes from Instantly, a cold email platform reporting on its own users' 2025 data. Its Cold Email Benchmark Report 2026 puts the average reply rate at 3.43%, with the top quartile at 5.5% or more and the top 10% at 10.7% or more. It also found that 58% of replies come from the first email, and it recommends four to seven touchpoints in total.
These are vendor figures from a vendor's own platform. Even so, the wide spread between average and top senders is worth noting, because it suggests that who you write to and what you say matter more than which tool sends the message.
Buyer preferences set the context. Gartner's 2026 sales survey found that most B2B buyers prefer a rep-free buying experience. An unsolicited email competes against that preference, so it has to earn attention through relevance rather than persistence.
Write fewer emails to fewer people
The setup that works looks almost old-fashioned. Start with a short list of accounts where something visible has changed: a new hire, a funding round, a new product line or a public complaint about the problem you solve. Replies to founders asking about this on Hacker News recommend the same scale: a normal mailbox on your own domain, a modest number of emails a day, sent only to people who visibly have the problem, each with one fact you can point to.
Keep the first email short. Instantly's data shows its strongest senders keep first-touch emails under 80 words. That leaves room for one sentence on why you are writing to this person, one on the problem, one on what you do and a low-effort ask.
Recipients notice generic AI copy immediately, because it could have been sent to anyone. Use AI to research the account and prepare a draft, then have a person check that every email contains a detail proving someone looked at the recipient's business.
Get the technical setup right before the first send
Mailbox providers now enforce deliverability rules. Google's sender guidelines ask senders to keep user-reported spam below 0.1% and never reach 0.3% or higher, measured daily in Postmaster Tools. Bulk senders above 0.3% are not eligible for mitigation until their spam rate stays below that level for seven consecutive days.
Microsoft has moved in the same direction. Since May 2025, domains sending more than 5,000 messages a day to Outlook.com, Hotmail and Live addresses must pass SPF, DKIM and DMARC, and mail that does not comply is routed to Junk first and may eventually be rejected.
A founder sending by hand at low volume sits far below those thresholds, but providers still judge every sender on authentication and complaints. A practical checklist:
- Send from a domain or subdomain you control, with SPF, DKIM and DMARC configured and aligned.
- Verify addresses before sending. Instantly recommends keeping bounce rates under 2%.
- Increase volume on new mailboxes gradually and keep daily volume per mailbox low.
- Give every recipient a clear way to opt out, and honour it immediately.
- Review Postmaster Tools and reply rates weekly, and pause any sequence that draws complaints.
Document your legal basis, especially in the UK and EU
B2B email in Europe comes with rules. The UK Information Commissioner's Office explains that under PECR the consent rule for electronic-mail marketing does not apply to corporate subscribers, but sole traders and some partnerships are treated as individuals. Opt-outs must still be respected, and UK GDPR still applies to personal data such as a named work email address.
In practice, write down why you are contacting each segment and how the message relates to the recipient's job, keep a suppression list that every tool checks, and remove anyone who asks. Rules differ between EU member states, so check the national position for each country you target and take legal advice where you are unsure.
Let automation handle the work around the email
Automation belongs around the send. Use it to find accounts with a trigger, enrich contact details, schedule follow-ups, log every reply in the CRM and route positive responses to the founder the same day. Keep human judgement on who receives an email and what it says.
That balance also keeps the channel sustainable. In a December 2025 Hacker News discussion, founders who felt intrusive doing outbound were steered towards relationships, referrals and the places where buyers already spend time. Cold email works best as one part of that mix, alongside the conversations and introductions that build trust.
What to do this week
- Check SPF, DKIM and DMARC on your sending domain and fix anything that fails or is not aligned.
- Build a list of 50 accounts with a visible trigger, and verify every address on it.
- Write a first email under 80 words with one specific detail per account, followed by three short follow-ups.
- Record your legal basis for each country and segment, and set up a shared suppression list.
- Connect replies to your CRM so every response is logged and answered within one working day.
Cold email in 2026 rewards senders who behave like a thoughtful person writing to one buyer. Keep the volume low and the technical setup clean, make every message specific, and measure the channel on meetings booked rather than emails sent. Stolos Digital builds CRM and follow-up automation for B2B teams that want the research and follow-up handled while every email stays personal.