Maximise Your Email Deliverability: The Role of SPF Records

Editor’s note: This article from August 2023 has been updated in October 2025 to reflect the latest best practices and ensure your SPF implementation meets current standards.

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If your email campaigns are struggling to reach your audience and keep landing in the spam folder, you’re not alone. Poor email deliverability plagues many businesses, eroding both marketing impact and sender reputation. Thankfully, there’s a proven solution: leveraging email authentication tools like SPF records.

This guide will explain what SPF records are, why they remain vital today, and walk you through current best practices, including real-world examples of implementation. You’ll gain the insight and confidence needed to strengthen your deliverability and ensure your messages land where they belong—right in your audience’s inboxes.

What Are SPF Records and Why Do They Matter?

SPF (Sender Policy Framework) is a global standard for email authentication. It enables domain owners to specify which mail servers can send emails on their behalf—a crucial defense against spam and phishing.

Key Benefits:

• Prevents spoofing: Only authorised IPs/domains can send as you.
• Boosts deliverability: Authenticated emails are less likely to go to spam.
• Protects brand trust: Reduces the risk that hackers impersonate you.

How SPF Works: SPF is implemented by publishing a TXT record in your DNS. When you send an email, the recipient’s mail server checks your domain’s SPF record to verify that the sending server’s IP is trusted. If the check passes, your message is more likely to reach the inbox. If not, it could be flagged as suspicious or blocked.

Implementation Example: Creating and Publishing an SPF Record

1. Identify All Authorised Senders Consider every system that sends on your behalf:
   • Your primary mail server (e.g., Microsoft 365, Google Workspace)
   • Third-party email platforms (e.g., Mailchimp, HubSpot)
   • Transactional email services (e.g., SendGrid, Amazon SES)
2. Drafting Your SPF Record The SPF record always starts with v=spf1. You can then add:
   • ip4: or ip6: for direct IP addresses.
   • include: for third-party sender domains.
   • An enforcement “qualifier” at the end (~all, -all, or ?all).
   Typical Example: v=spf1 ip4:203.0.113.5 include:_spf.google.com include:sendgrid.net ~all
   • This allows mail from the IP 203.0.113.5, Google Workspace, and SendGrid.
3. Add the SPF Record to DNS Go to your DNS hosting provider (e.g., GoDaddy, Cloudflare, AWS Route 53):
   • Add a new TXT record at your domain’s root (@ or blank).
   • Enter your complete SPF string as the value.
   • Save and allow time for DNS propagation (usually up to 48 hours).
4. Verify and Test Use a modern deliverability tool to check your configuration, such as:
   • MXToolbox SPF Lookup
   • Google Admin Toolbox

Minimise Errors: Common SPF Implementation Pitfalls

1. No SPF or Outdated Records

Without an SPF record, or if your record omits current senders, mail may be flagged as spam or rejected. Review your sender sources quarterly, especially as team tools change.

2. Multiple SPF Records

Only one SPF TXT record is valid per domain. Multiple records will break authentication. Always consolidate everything into a single record.

3. Exceeding the “10 DNS Lookup” Limit

SPF checks can only perform up to 10 DNS lookups during evaluation. Using too many include: statements can hit this limit and invalidate the check.

Tip: Use tools like DMARC Analyzer’s SPF Checker to ensure you’re within the limit.

4. Forget to Update After Vendor Changes

If you switch or add new mail providers and don’t update your SPF record, legitimate emails may fail SPF validation.

5. Incorrect Syntax

Even a tiny syntax error (e.g., missing a space) can cause the SPF record to fail entirely. Always validate after editing.

Beyond SPF: Combine with DKIM and DMARC

For robust email authentication, SPF is just the beginning:

• DKIM (DomainKeys Identified Mail): Adds a digital signature to outgoing messages, ensuring they’re not tampered with in transit.
• DMARC (Domain-based Message Authentication, Reporting & Conformance): Allows you to publish a policy on how receiving servers should treat failed SPF/DKIM checks—giving you visibility through aggregate reports and helping you block spoofed messages.

Example of Setting a DMARC Policy TXT:

v=DMARC1; p=quarantine; rua=mailto:dmarc-reports@yourdomain.com; adkim=s; aspf=s;

This tells receiving servers to quarantine failed messages and send you reports.

Best Practices for Ongoing SPF Management

• Review Quarterly: Update SPF records as you add, remove, or change email providers.
• Test After Every Change: Always use online SPF validation tools before and after edits.
• Monitor Deliverability: Watch for unexpected drops in open rates or increases in spam complaints.
• Document Sender Infrastructure: Keep an internal document listing all systems/teams with mail-sending authority.

Troubleshooting SPF Issues

• Email fails SPF but should pass: Double-check the source IP or provider’s authorized domain is included (e.g., did you update the entry after integrating a new API for transactional emails?).
• Emails marked as spam: Check for a “softfail” or “neutral” SPF result. Use ~all for soft fail during testing, switch to -all once validated.
• SPF syntax error: Revalidate with tools like MXToolbox or Google’s CheckMX.

If issues persist, your email service provider or an email deliverability consultant can help identify DNS setup or policy problems.

Conclusion: SPF as a Foundation for Modern Email Delivery

In today’s threat landscape, email authentication isn’t optional—it’s essential. Correctly configuring your SPF record is one of the foundational steps in an effective email strategy. When combined with DKIM and DMARC, you build an authentication framework that maximizes inbox placement, minimizes spoofing, and protects both your business and your recipients.

Keep your records current, test regularly, and make SPF management a routine part of your communications best practices. If you’re systematic and proactive, your business can reach inboxes—and customers—more reliably than ever.

Need secure business email? SaneChoice Business Email comes with full instructions on how to setup your SPF record. Learn more about our Business Email.