How to Set Up SPF for Fastmail

Authorize Fastmail to send email on behalf of your custom domain by adding the correct SPF include.

Quick Answer — The Record You Need

Record Type

TXT

Host / Name

Value

v=spf1 include:spf.messagingengine.com ~all

Fastmail's parent company is Messaging Engine. The SPF include uses their infrastructure domain.

Step-by-Step Setup

Log in to Fastmail

Go to fastmail.com and sign in to your account.

Navigate to domain settings

Go to Settings > Domains. Select your custom domain.

View required DNS records

Fastmail displays all required DNS records including SPF, DKIM, and MX.

Add the SPF record

Add a TXT record with the SPF include for Fastmail.

v=spf1 include:spf.messagingengine.com ~all

Verify in Fastmail

Fastmail will check your DNS records and show verification status.

Before & After

Before

v=spf1 ~all

After

v=spf1 include:spf.messagingengine.com ~all

Common Gotchas

Fastmail uses spf.messagingengine.com, not spf.fastmail.com. Messaging Engine is Fastmail's parent company.
If you also use Fastmail for sending from aliases, all aliases use the same SPF include.
Fastmail provides a complete set of DNS records (MX, SPF, DKIM, DMARC). Set them all up together for best results.

Verify Your Setup

After adding your DNS records, use our free SPF checker to verify everything is configured correctly. DNS changes typically propagate within minutes, but can take up to 48 hours.

Frequently Asked Questions

What SPF record do I need for Fastmail?

Add include:spf.messagingengine.com to your SPF record. This is Fastmail's sending infrastructure domain.

Why does Fastmail use messagingengine.com for SPF?

Messaging Engine Pty Ltd is Fastmail's parent company. Their email infrastructure runs under the messagingengine.com domain.

Do I also need MX records for Fastmail?

Yes. Fastmail requires MX records pointing to in1-smtp.messagingengine.com and in2-smtp.messagingengine.com for receiving email.