Sender Policy Framework (SPF) – A Simple Guide to Email Authentication

With the rising threat of email spoofing, spam, and phishing attacks, securing your email domain is more important than ever. One of the most effective tools in the fight against fake emails is SPF, or Sender Policy Framework.

In this article, we’ll walk you through what SPF is, how it works, why it matters for your business, and how to configure it correctly to improve your email deliverability and security.

What Is SPF (Sender Policy Framework)?

SPF is an email authentication protocol that helps protect your domain from unauthorized use—especially email spoofing.

When someone sends an email from your domain, SPF allows the receiving mail server to check if the email was sent from an authorized server. If it wasn’t, the server can flag or reject the email.

Why SPF Is Important

Prevents Spoofing – Ensures that only authorized servers can send emails using your domain.
Improves Deliverability – Boosts the chances that your emails land in the inbox, not the spam folder.
Protects Your Brand – Stops attackers from using your domain to trick customers or partners.
Supports DMARC and DKIM – Works together with other protocols for better email authentication.

How Does SPF Work?

Here’s a simple explanation of how SPF works step-by-step:

You add an SPF record to your domain’s DNS settings.
When your domain sends an email, the receiving server checks your SPF record.
The receiving server compares the sending IP to the authorized IPs listed in the SPF record.
If the IP is on the list, the email passes SPF. If not, it may be marked as spam or rejected.

What Is an SPF Record?

An SPF record is a DNS TXT record that contains a list of authorized mail servers for your domain.

Here’s an example SPF record:

v=spf1 ip4:192.0.2.1 include:_spf.google.com -all

Let’s break it down:

v=spf1: Indicates this is an SPF version 1 record.
ip4:192.0.2.1: Authorizes this IP to send emails.
include:_spf.google.com: Includes Google’s mail servers (used with Gmail, Google Workspace).
-all: All other IPs are not allowed and will fail SPF.

How to Set Up an SPF Record for Your Domain

Step 1: Identify Your Email Sending Sources

List all platforms and services you use to send email from your domain, such as:

Your hosting provider (cPanel, Hostinger, etc.)
Google Workspace or Microsoft 365
MailChimp, Sendinblue, or any third-party tool

Step 2: Create Your SPF Record

Write your SPF record in a TXT format. Here’s an example if you use Gmail and Mailchimp:

v=spf1 include:_spf.google.com include:servers.mcsv.net -all

Step 3: Add the SPF Record to DNS

Log in to your domain registrar (e.g., GoDaddy, Namecheap).
Go to the DNS settings or DNS zone editor.
Add a new TXT record.
Name/Host: @ or leave blank (for root domain)
Type: TXT
Value: Your SPF record
TTL: Use default (e.g., 3600 seconds)

Step 4: Test Your SPF Record

Use tools like:

These tools help validate if your SPF record is correct and functioning.

Best Practices for SPF Records

✅ Keep it short – Too many DNS lookups can break SPF (limit: 10).

✅ Use include: carefully – Only add trusted third-party services.

✅ Always end with -all or ~all – This tells servers what to do with unauthorized senders.

-all: Fail (strict)
~all: Soft fail (lenient, often used during testing)

✅ Avoid multiple SPF records – Only one SPF record per domain is allowed. Combine them.

Common SPF Errors to Avoid

Having multiple SPF records – Combine into one.
Incorrect syntax – A missing space or semicolon can invalidate the record.
Forgetting to update when adding a new service – Always update SPF when you start sending emails from a new platform.
Too many DNS lookups – Stay under the 10-lookup limit, or your record will fail.

SPF vs. DKIM vs. DMARC

Protocol	Purpose	Works With
SPF	Authorizes sending servers	DNS
DKIM	Signs emails with a digital key	DNS, Email headers
DMARC	Uses SPF & DKIM for reporting & enforcement	DNS

They are not alternatives, but complementary tools. Using all three gives you the best protection against spam and spoofing.

Benefits of SPF for SEO and Email Marketing

While SPF isn’t directly tied to SEO rankings, it plays a critical role in email deliverability — which affects your email marketing success.

Higher inbox placement = More engagement
Fewer emails in spam = Lower bounce rate
Secure domain = Increased trust in your brand

Search engines and email providers value domain reputation. Poor email practices can affect this reputation, indirectly impacting SEO.

The Sender Policy Framework (SPF) is a must-have tool for anyone who sends emails from their own domain. It protects your reputation, ensures your emails reach their destination, and helps fight against phishing and spoofing attacks.

With a properly configured SPF record, your emails are more secure, trustworthy, and less likely to end up in the spam folder.

Don’t forget to pair SPF with DKIM and DMARC for full email protection.