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Why are my emails suddenly going to spam?

Your emails reached customers fine for years, and now they're landing in spam. Something changed: in your setup, in your sending, or in the rules at Gmail, Yahoo and Microsoft. Here's how to find what.

Rather not do this yourself? We find and fix what's sending your email to spam for $199. If there's nothing to fix, you don't pay.

Email us your domain Free check

Start here

Run your domain through the free check, then send yourself an email at Gmail and choose ⋮ → Show original. Whether SPF, DKIM and DMARC say PASS or FAIL tells you which causes below to look at first.

1. A new tool broke your SPF record

This is the most common one. Someone set up a new booking system, newsletter tool or website plugin, and its setup guide said "add this SPF record". Now your domain has two SPF records, and two records break SPF for all your mail. Or the new include pushed the record past its limit of 10 DNS lookups, with the same result. The fix is to merge everything into one record and remove includes you no longer use.

2. The rules changed at Gmail, Yahoo and Microsoft

From February 2024, Gmail and Yahoo required SPF or DKIM for every sender, and SPF, DKIM and DMARC for bulk senders. Microsoft followed for Outlook.com and Hotmail: from May 5, 2025, domains sending more than 5,000 messages a day to Microsoft's consumer mailboxes must pass SPF and DKIM and publish DMARC, or get rejected with error 550 5.7.515. Mail that got through for years without DKIM or DMARC now often doesn't. If Show original shows no DKIM for your domain, or no DMARC, this is likely your cause.

3. Your email provider changed something

A moved domain, a switch from one email provider to another, or a change of DNS host can leave old records behind or drop new ones. DKIM is the one most often lost: the old provider's key stays in DNS, and the new provider's key never gets added. Check that DKIM shows your domain and your current provider.

4. Your domain or IP is on a blacklist

If one of your mailboxes was hacked and used to send spam, or your website was compromised, your domain or your server's IP may now be on a blocklist such as Spamhaus. Check your domain and sending IP with a blacklist lookup. Once you've fixed the cause, most lists have a removal request form. If you use a big provider like Google or Microsoft, an IP listing is their problem, not yours, but a domain listing is still yours.

5. A hacked mailbox

Look at your Sent folder and your provider's sign-in log for anything you don't recognise. A compromised account sending hundreds of spam messages ruins a domain's reputation in hours. Change the password, turn on two-factor sign-in, and remove any forwarding rules you didn't create.

6. Your sending changed

A sudden mailing to an old customer list, a big jump in volume, or a new email template full of links and images can all trigger filters. So can many people marking your messages as spam: Gmail's guidance for bulk senders is to keep the complaint rate below 0.3%. If the change started after a campaign, that's probably it.

7. It's only one customer

If one customer, or one company, is suddenly not getting your mail and everyone else is, the issue is likely their filter: a new security product, a stricter policy, or someone who marked you as spam. Ask them to check their junk or quarantine and add you to their safe senders.

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We check everything above, fix your SPF, DKIM and DMARC, test real emails to Gmail, Outlook and Yahoo, and tell you exactly what went wrong. $199, and if there's nothing to fix, you don't pay.