Why your emails land in spam: SPF, DKIM and DMARC in plain English, before the Black Friday send
Black Friday is 27 November. A 20-minute check of SPF, DKIM and DMARC, what Gmail and Yahoo now expect from senders, and where AI helps, so your offer lands in the inbox.
Why your emails land in spam: SPF, DKIM and DMARC in plain English, before the Black Friday send
By Jason Sibley
What this is for, and who it's for
Black Friday is Friday 27 November 2026. That's about five weeks away, but DNS changes take time to show up and sender reputation takes time to build. Check this week, not the night before.
This guide is for owners who send offers and newsletters from their own domain (hello@yourshop.co.uk, say) through Mailchimp, Klaviyo, Shopify Email, Google Workspace or Microsoft 365. If your emails sometimes land in spam, or you've never checked your domain's sending set-up, it's for you.
You don't need to be technical. Allow about 20 minutes, with a login for your email platform and the name of whoever looks after your domain. This is practical guidance, not technical or legal advice. If something looks unfamiliar, ask your web person or your email platform's support team.
The three records, in plain English
The NCSC (the National Cyber Security Centre) explains all three on its email security and anti-spoofing page:
- SPF is a published list of the servers allowed to send email for your domain.
- DKIM is a digital signature on your email. It