SPF is one of the main methods email servers use to authenticate emails. By checking your list of IP addresses, email services and ISPs can identify whether the message came from a trusted server. If you send email from a custom domain (for example, you can list the IP addresses (new window) of the mail servers authorized to send your mail. Sender Policy Framework (SPF) is an email authentication protocol that allows you to specify the servers authorized to send mail from your domain, making it harder for fraudsters to spoof (forge) your address. What is Sender Policy Framework (SPF)? What is SPF used for? How SPF differs from DKIM and DMARC How does SPF work? What is an SPF record? SPF and mail forwarding Why use SPF? Beat spammers and scammers Improve email deliverability Boost your domain reputation Easy SPF authentication with Proton Mail What is Sender Policy Framework (SPF)? We explain SPF, how it works, and why you need it to help protect your domain and ensure your messages are delivered. Used with DKIM and DMARC (new window), SPF is one of the main ways internet service providers (ISPs) and email platforms identify and block spam and phishing attacks.

Learn how it works and how it helps to protect your email domain.

Sender Policy Framework (SPF) is an email authentication method that verifies that a message has been sent from an authorized mail server.

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