What is SPF (Sender Policy Framework)?

SPF (Sender Policy Framework) is a system to help domain owners specify the servers which are permitted to send mail from their domain. The aim is that other mail systems can then check to make sure the server sending email from that domain is authorized to do so - reducing the chance of email spoofing, phishing schemes and spam.

How do I use them with AuthSMTP?

SPF records need to be added to the DNS records for a domain name and need to be tailored to you or your company so we can only provide guidance on configuring your SPF record to use our service - you need to consider what other sources of email may need to be included in your SPF record.

If you already have a SPF record setup on your domain name you just need to add:


... to your existing SPF record (before the -all).

If you don't have one already setup a 'typical' SPF record could be:

"v=spf1 a mx include:authsmtp.com ~all"

This will by default allow email from the default IP address for your domain (typically your web server), any hosts at your domain (i.e.hostname.your-domain-name.com) and all the IP addresses we currently use for sending your email.

There are 4 options for 'all' - we recommend using '~all' to start with and then consider the strictest '-all' when you are 100% sure the SPF records you have chosen are accurate.

More information about SPF

For information on the syntax and format of SPF records please see:

Other Questions