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What is SPF?
Reviewed by the Free Domain Mail editorial team · Updated
SPF is the starting point for sender authentication. It makes the list of authorised sending services visible in DNS.
What an SPF record does
SPF is a TXT record that lists the services allowed to send email for a domain.
Publish exactly one SPF record at the root of the domain, combine authorised services, and stay within the DNS lookup limit.
A safe starting record
A simple record such as v=spf1 include:amazonses.com -all only works when Amazon SES is the only service sending for the domain.
If Google Workspace, Microsoft 365, a newsletter service or a website also sends mail, each legitimate sender must be accounted for in the same record.
Common mistakes to avoid
- Publishing two SPF TXT records at the same hostname.
- Adding includes for services that no longer send for the domain.
- Using -all before every legitimate service has been tested.
Frequently asked questions
Can I have more than one SPF record?
No. Merge all permitted senders into one TXT record at the root hostname.
Does SPF alone stop spoofing?
No. Pair it with DKIM and DMARC for stronger protection.
Technical references
Primary specifications and provider documentation relevant to this guide: