SPF, DKIM and DMARC for Intercom

Short answer: Intercom mail passes Gmail, Yahoo and Microsoft checks when you turn on DKIM with your own domain and publish a DMARC record at _dmarc (start with p=none). The exact records and clicks are below.

SPF	—	Not needed on your root domain: the return-path CNAME gives Intercom a bounce address on your domain, so SPF passes and aligns there.
DKIM	CNAME / TXT	CNAME `intercom._domainkey` → `<id>.dkim.intercom.io` (the id is unique to your workspace), plus a second CNAME for the return path. Copy both from Intercom.
DMARC	TXT at `_dmarc`	v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com Start with `p=none` and a mailbox you read, or a free report address that turns the reports into a dashboard; build your own.

Step by step

In Intercom open Settings → Channels → Email → Domains & addresses and verify your sending address.
Click Authenticate your domain to see the two CNAME records and the DMARC record.
Add them at your DNS host: Intercom's Name goes in the host field, Value in the target field.
Wait for DNS (usually a few hours, up to 72), then click Finish setup and Validate authentication.

Mistakes that break it

Intercom requires a DMARC record of at least p=none on your domain.
On Cloudflare, set both CNAMEs to DNS only (grey cloud), not proxied.
Both records must be CNAMEs. A leftover TXT record at the same name breaks them.
Developer workspaces can't send outbound email at all, whatever your DNS says.
Bounces with 550 5.7.509 mean your DMARC policy rejected mail that wasn't authenticated: check the DKIM and return-path records.

Check that it worked

After the fix, keep an eye on it: free DMARC monitoring shows every service that sends mail as your domain and which ones fail, in plain English.

Rather not touch DNS? I set up SPF, DKIM and DMARC without breaking your other senders, with a before/after report.

Get it fixed on Fiverr

Prefer to do it yourself? Get the step-by-step Fix Kit ($15) – 19-page guide, checklist, 20+ providers.

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