An SPF record is used to verify that the issuing IP has the right to send emails. It helps prevent fraudulent use of your domain name and is especially effective against phishing attacks.
A domain may have only one SPF record. Having more than one SPF record can have a negative impact on the reputation of your domain, and can lead to deliverability problems and cause your emails to end up in spam. If you need to include multiple SPF records for your domain, you should always merge them together.
To merge multiple SPF records, you need to combine the different parts of the records. For example, you combine the SPF records for Google Workspace and Brevo:
v=spf1 include:_spf.google.com ~all
v=spf1 include:spf.brevo.com mx ~all
An SPF record always starts with the version: v=spf1. Then we add both “include” mechanisms to our new record: v=spf1 include:_spf.google.com include:spf.brevo.com. The Brevo SPF record contains an “mx” mechanism, so we need to include it in our new record as well: v=spf1 include:_spf.google.com include:spf.brevo.com mx.
Finally, we need to define how emails should be handled when a sender does not match any of the previous mechanisms. This is done with the “all” mechanism: v=spf1 include:_spf.google.com include:spf.brevo.com mx ~all. This new SPF record now replaces the old record. It allows both Google Workspace and Brevo to send emails with your domain name, while blocking all other senders with “~all”.