Why Is My Business Email Going to Spam? (And How to Fix It)

Send a test to yourself from hello@yourdomain.co.uk. It arrives instantly, so everything seems fine. Then a customer says they never got it. This is the single most common email problem small businesses hit, and it is almost always invisible from the sending side.

The three records, and what each does

SPF — "may I send as this domain?"

SPF lists the servers permitted to send email using your domain name. It is a single DNS TXT record. Without it, or if it includes servers you don't control, senders can't verify you and will often mark you as spam.

DKIM — "this email wasn't tampered with"

DKIM adds a cryptographic signature to outgoing mail using a private key, and publishes the matching public key in DNS. If the signature checks out, the receiving server knows nobody altered the message in transit. It is the strongest single signal for Gmail and Microsoft.

DMARC — "what to do if SPF or DKIM fails"

DMARC tells receiving servers what to do when neither SPF nor DKIM passes: report it, quarantine it, or reject it. It also includes a p= policy telling senders where to send reports. Publishing DMARC is what makes the other two enforceable rather than decorative.

The mistake that breaks everything

The quick checklist

1. Send a test to Gmail and check the raw headers. Gmail shows "Authenticated as" near the top. If it doesn't say your own domain, something's wrong. Send to check-auth@verifier.port25.com for a fuller report.
2. Confirm there is exactly one SPF record. Use a checker like MXToolbox or mail-tester.com.
3. Verify DKIM is enabled in your mail host's settings, and that its selector v=DKIM1; exists in DNS.
4. Check your sending reputation. Email is scored per-IP. If your mail server has sent spam before — or is shared with people who have — your score is damaged.
5. Look for a spam folder. Some addresses go straight to junk with no notification. Ask a few customers to check.
6. Never send from a free address. "From: yourname@gmail.com" with your domain as a reply-to is the fastest way to lose trust. Gmail and Microsoft treat it as spoofing.

Reasons mail disappears that aren't DNS

• The recipient's mail server is blocking you outright. You'll get a bounce message explaining why. Read it — it's often a spam policy, not a fault.
• Your server IP is on a blocklist. Check it. Shared hosting addresses can land on blocklists without the host telling you.
• Your forms are being flagged as spam by filters because the message is identical every time and comes from the same IP as your marketing mail.
• Attachments are being blocked by corporate filters. Common with executables and archives, and increasingly with anything unusual.
• You're missing a DMARC record with a sensible policy, so senders have no instruction and default to distrust.

Fixing it properly

If your mail is important — and for a business taking enquiries or sending quotes, it is — we can configure SPF, DKIM and DMARC correctly for your domain and verify them, so you're sending with proper authentication from day one. We also run a blacklist and deliverability check as part of our monthly security audit.

There is a genuine argument for a dedicated transactional mail service for anything automated. Bulk or application email sent through ordinary web hosting gets filtered harder, because hosting IPs have no business sending newsletters. If you send anything automated, that separation matters more than any DNS record.

One thing to be careful about

Start DMARC at p=none with a rua address so you collect reports, look at them for a few weeks, then tighten to p=quarantine and eventually p=reject. Jumping straight to p=reject before SPF and DKIM are genuinely correct will silently break legitimate mail — including password resets and payment confirmations you didn't know were running through this domain.