SPF Record Guide for Business Email

SPF (Sender Policy Framework) is a TXT record listing which systems may send mail as your domain. Receivers check it to reduce spoofing and improve trust in outbound mail from MailShrine.

Critical rule: publish only one SPF TXT per domain. Merge every include: into a single v=spf1 … line.

Real-life example: Northwind Apps

Zara added MailShrine SPF beside an old website-host SPF. Gmail started hard-failing outbound (“permerror: too many SPF records”). Merging includes fixed it in one DNS edit.

SPF in plain language

MailShrine shows the include string for your workspace — paste that, then merge with tools you already use (ESP, ticketing).

What you need

DNS edit rights + list of every service that sends as @yourdomain + MailShrine Domains panel.

Step 1: Inventory existing SPF

Search TXT at @ for any v=spf1 line.

Step 2: Copy MailShrine’s include

From Domains authentication section.

Step 3: Merge into one record

Example shape (illustrative):

v=spf1 include:mailshrine-example ~all

If you also send via a marketing tool, add its include: before ~all. Stay under SPF’s lookup limits (keep includes tight).

Step 4: Delete the duplicate SPF

Never leave two v=spf1 TXT rows.

Step 5: Recheck outbound

Send a test; confirm headers show SPF pass once DNS propagates (timing).

Checklist

• Only one SPF TXTCompleted
• MailShrine include presentCompleted
• Other senders mergedCompleted
• Header check passedNot completed

Common mistakes

1. Two SPF records.
2. Ending with +all (everyone authorized — dangerous).
3. Forgetting marketing ESPs in the include list.
4. Editing DKIM when SPF was the failure (difference guide).

Next steps

• DKIM · DMARC · Why mail goes to spam

Citations & References

• Reference: Google: Email sender guidelines
• Reference: Cloudflare Learning Center: DNS records
• Reference: ICANN: What is DNS?

Written by Daniel O., Email Authentication Specialist. Daniel fixes deliverability issues caused by duplicate SPF and missing includes.