Email marketing that works is built in this order: delivery, permission, relevance, then copy. If your domain isn't authenticated, mailbox providers may send your emails to spam however good they are. If people didn't clearly agree to hear from you, they mark you as spam and teach the providers to do it for everyone. Get those right, send fewer and more useful emails, and measure replies and clicks rather than opens.
Most email advice starts with subject lines. That's the last ten percent of the job.
Why does deliverability come first?
An email nobody receives has no subject line worth optimising. The large mailbox providers decide whether your message reaches the inbox, the spam folder or nowhere, and they decide largely on two things: can they verify it's really from you, and do recipients want it.
Authenticate your domain
Three DNS records do the verifying:
- SPF lists which servers may send email for your domain.
- DKIM signs each message, so a provider can check it wasn't forged or altered.
- DMARC tells providers what to do when a message fails those checks, and sends you reports about who is sending in your name.
These aren't optional extras any more. Google's sender guidelines require every sender to Gmail to authenticate, and bulk senders (around 5,000 messages a day to Gmail addresses) to have SPF, DKIM and DMARC in place, offer one-click unsubscribe, and keep their reported spam rate below 0.3%. Yahoo set out matching requirements. If you send marketing email from your domain, set all three up before your next campaign.
Keep marketing and transactional mail apart
Receipts, booking confirmations and password resets have to arrive. Newsletters are allowed to be ignored. Send them from different subdomains, say one for transactional mail and one for marketing, so a newsletter that annoys people can never drag your receipts into spam with it.
What does real permission look like?
Permission is the part that keeps working long after the setup.
- Opt-in means they chose it. A customer who bought from you once didn't necessarily ask for a weekly newsletter. A pre-ticked box isn't a choice.
- Unsubscribing works instantly and permanently. One click, no login, no "are you sure?" maze. Every unsubscribe you make difficult turns into a spam complaint instead, and complaints hurt every future send.
- "Not on the do-not-contact list" isn't consent. An address you haven't been told to stop emailing is still an address that never asked. Build your list from people who said yes, and keep the record of when and how.
- Clean the list. Addresses that bounce, and people who haven't opened anything in a long time, drag down how providers see you. Remove them, or ask them once whether they still want to hear from you.
How do you make emails people want?
With permission and delivery handled, relevance does the rest:
- Segment by what people did, not who they are. "Booked last month", "asked about pricing but didn't buy", "a customer for two years". Behaviour predicts interest far better than age or job title.
- One email, one point, one ask. An email trying to announce three things gets none of them read.
- Write like a person. A plain, short email from a named person at the business often outperforms a designed newsletter, because it reads like a message rather than a broadcast.
- Send when there's something to say. A useful email a month beats a filler email a week.
- Make replying welcome. Replies are the best signal there is: providers notice them, and they start real conversations.
What should you measure?
Not open rates, mostly. Since Apple's Mail Privacy Protection arrived in 2021, Apple Mail can load emails in the background whether or not anyone reads them, which counts as an "open". Open rates now overstate attention by an amount you can't know.
Measure what people did:
- Clicks on the one link that mattered.
- Replies.
- The outcome: bookings, purchases, enquiries traced back to the email.
- Spam complaints and unsubscribes, as early warnings.
What we're building at Quantum Accord
Email is part of the Business OS we're building, and its sending already works on the rules above. Every message is checked against the unsubscribe, complaint and bounce list before it goes out, and a suppressed address is refused, never sent "just this once". Marketing mail carries the one-click unsubscribe headers mailbox providers look for. Every unsubscribe link is signed, so one person can't unsubscribe someone else. It's in development and not yet available, and we won't present it as available until it is.
A checklist before your next campaign
- SPF, DKIM and DMARC are set up for the domain you send from.
- Marketing and transactional email go out from different subdomains.
- Every address on the list opted in, and you can say when and how.
- Unsubscribe is one click and takes effect immediately.
- This email has one point and one ask.
- You'll judge it by clicks, replies and outcomes, not opens.
The best email lists are small, permission-built and genuinely missed when they stop. That's the asset, not the size of the list.
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