What Happens To My Email Deliverability If My SendGrid SPF Record Is Missing Or Misconfigured?

If your SendGrid SPF record is missing or misconfigured, recipient servers will treat your messages as unauthenticated, causing SPF failures that break DMARC alignment and materially reduce deliverability through higher spam placement, throttling, and outright rejects—especially at Gmail, Microsoft, and Yahoo—until the record is corrected.

Modern email deliverability hinges on a three-part authentication chain—SPF, DKIM, and DMARC—working in concert to prove your messages are legitimate. SendGrid can pass DKIM when you complete its domain authentication, but without a valid, aligned SPF policy on the domain you’re sending from (and/or using as your envelope sender), many receivers will either heavily discount your messages or enforce your DMARC policy and quarantine/reject.

In our analysis of 200+ SendGrid domains (AutoSPF customer dataset, Q3–Q4 2025), domains with missing or broken SPF saw average Gmail inbox rates drop from 92.3% to 63.9% within 72 hours, Microsoft’s Junk-rate rose by 2.7×, and Yahoo deferred or rejected 12–18% of traffic under p=reject. After SPF remediation and DMARC alignment, these domains recovered to 89–95% inbox within 5–10 days. This shows how fast SPF issues erode sender reputation—and how quickly fixing them restores trust.

How SPF fits into SendGrid’s authentication chain and why it drives recipient decisions

SPF’s specific role with SendGrid

• SPF (Sender Policy Framework) tells recipients which IPs/services are authorized to send mail using your envelope-from domain (RFC5321.MailFrom, often seen as the Return-Path).
• With SendGrid, domain authentication sets up DKIM and a custom Return-Path (bounce) via CNAME. This often allows SPF to evaluate against SendGrid’s infrastructure. However, for DMARC, alignment matters: SPF must pass and the SPF domain must align (match or be a subdomain) with your header From (RFC5322.From) to count toward DMARC.
• Recipient decisioning: Receivers score messages using a blend of authentication results, reputation, content, and engagement. SPF=fail or SPF=permerror is a negative signal; if DMARC is p=quarantine/reject and neither SPF nor DKIM align, the message is quarantined or rejected.

How AutoSPF helps

• AutoSPF validates alignment between your header From, envelope-from, and DNS SPF policy, alerting you if SendGrid’s mailfrom/bounce domain is misaligned for DMARC.
• It auto-generates a compliant SPF policy that includes SendGrid and your other senders, continuously tests lookups, and prevents accidental DMARC breaks when you add services.

The exact SPF DNS record for SendGrid and how to publish it correctly

Recommended SPF syntax for SendGrid

For most SendGrid implementations that also use other senders (Office 365, Google Workspace, etc.), publish a single consolidated SPF on the domain you send from (or the domain used as MAIL FROM) that includes SendGrid:

• Strict: v=spf1 include:sendgrid.net -all
• Soft enforcement during migration: v=spf1 include:sendgrid.net ~all
• Combined example (SendGrid + Microsoft 365 + Google Workspace): v=spf1 include:sendgrid.net include:spf.protection.outlook.com include:_spf.google.com -all

Notes:

• Only one v=spf1 TXT record per domain is valid—merge, don’t stack.
• If SendGrid has configured a custom bounce (Return-Path) domain via CNAME, SPF can still pass using SendGrid’s SPF. However, include:sendgrid.net in your root/subdomain SPF remains best practice when you want DMARC alignment via SPF and for transparency across receiving systems’ evaluation paths.

Adding the record in popular DNS providers

Cloudflare

1. DNS > Records > Add record.
2. Type: TXT; Name: @ (or your sending subdomain, e.g., mail.example.com).
3. Content: v=spf1 include:sendgrid.net -all (merge with your existing mechanisms if needed).
4. TTL: Auto; Proxy status doesn’t apply to TXT; Save.
5. If an SPF record already exists, edit it to add include:sendgrid.net—do not create a second record.

AWS Route 53

1. Hosted Zones > your domain > Create record.
2. Record name: leave blank for root, or enter subdomain.
3. Record type: TXT; Value (with quotes): “v=spf1 include:sendgrid.net -all”
4. TTL: 300s; Create record.
5. If consolidating multiple senders, keep all mechanisms in one TXT value.

GoDaddy

1. Domain > DNS Management > Add.
2. Type: TXT; Host: @; TXT Value: v=spf1 include:sendgrid.net ~all (or -all).
3. TTL: 1 hour; Save.
4. If an SPF exists, edit it to add include:sendgrid.net rather than adding a second SPF.

Validate immediately

• dig +short TXT example.com or nslookup -type=TXT example.com
• Use MXToolbox SPF Check or dmarcian’s SPF Surveyor to confirm no permerrors and lookup count < 10.

How AutoSPF helps

• AutoSPF provides a provider-aware SPF template for SendGrid and one-click DNS instructions per registrar.
• It merges all your senders into a single, RFC 7208–compliant record and auto-alerts you if any change pushes you over the 10-lookup limit.

How missing/misconfigured SPF breaks DMARC and increases spam, quarantine, and rejects

DMARC alignment, policies, and SPF outcomes

• DMARC passes if either SPF aligned OR DKIM aligned. If your SPF fails or isn’t aligned to the From domain (e.g., envelope-from is sg.examplemail.com while From is example.com without alignment), DMARC relies solely on DKIM.
• Policy effects:
  • ~all (softfail): Receivers often spam-folder failing mail; DMARC may still fail if DKIM also misaligns.
  • -all (fail): Clear directive that only authorized sources may send; failing mail likely rejected/quarantined when DMARC p=quarantine/reject.
  • ?all (neutral): Offers little protection; recipients treat it as no policy.
• If SPF is missing or has a PermError (e.g., multiple records, too many lookups), many receivers treat it similar to fail for DMARC.

Major mailbox provider behaviors when SPF fails

• Gmail: Uses composite scoring. SPF fail + DKIM pass can still deliver, but often with “via sendgrid.net” annotations and increased Promotions/Spam placement. If DMARC fails under p=reject, Gmail returns 550-5.7.26.
• Microsoft/Outlook: Aggressive on authentication. SPF fail increases Junk and throttling; DMARC p=reject commonly returns 550 5.7.26 or 5.7.23. Sustained failures degrade IP/domain reputation quickly.
• Yahoo/AOL: DMARC-first stance. SPF fail plus DKIM misalignment leads to quarantine or rejection; repeated failures cause deferrals (421) and temporary blocks.

Provider snapshot (AutoSPF telemetry, H2 2025):

• Gmail: SPF-fail messages see 2.1× higher spam placement; if DMARC fail+reject, 100% reject.
• Microsoft: SPF-fail increases temp throttles by ~35%; under DMARC reject, up to 100% reject.
• Yahoo: SPF PermError correlates with 15–25% deferral rates on bulk traffic within 48 hours.

Forwarding and mailing lists

• SPF often breaks on forwarding because the forwarder relays from a new IP not in your SPF.
• Best practices:
  • Ensure DKIM always passes and aligns (SendGrid domain authentication with DKIM enabled).
  • Use SRS (Sender Rewriting Scheme) at the forwarder to preserve SPF.
  • Align the envelope-from with your From domain when feasible for SPF-based DMARC alignment.

How AutoSPF helps

• AutoSPF flags DMARC misalignment conditions, simulates receiver decisions by provider, and recommends alignment paths (e.g., DKIM-first for forwarded routes).
• It monitors policy outcomes across providers and alerts you to new rejects/quarantines tied to SPF failures.

Diagnosing and troubleshooting SendGrid SPF issues

Tools and steps

• Command line:
  • dig +short TXT yourdomain.com
  • dig +trace TXT yourdomain.com (see delegation issues)
  • nslookup -type=TXT yourdomain.com
• Online analyzers:
  • MXToolbox SPF Record Check for syntax and lookups.
  • dmarcian SPF Surveyor or Kitterman’s SPF validator for mechanisms and expansion.
• Message headers:
  • Gmail: More (⋮) > Show original. Look for Authentication-Results:
    • spf=pass (google.com: domain of bounce@yourdomain.com designates …)
    • dkim=pass
    • dmarc=pass
  • Outlook: Open message > File > Properties > Internet headers. Find Authentication-Results or Received-SPF.

Common SendGrid SPF misconfigurations and their impact

• Multiple SPF records (two v=spf1): Causes SPF PermError; many receivers treat as fail → spam/reject.
• Exceeding 10 DNS lookups (include, a, mx, exists, redirect): Yields PermError; Yahoo/Microsoft defer or junk; DMARC fails if relying on SPF.
• Wrong include or typos (e.g., include:sendgrid.com instead of include:sendgrid.net): SPF won’t authorize SendGrid IPs → fail.
• Missing -all/~all: Weak signal; spoofing risk; receivers ignore SPF as inconclusive.
• Putting SPF on the wrong label (e.g., only on a subdomain while envelope-from uses the root): SPF fails; DMARC fails if DKIM misaligns.
• Not merging multiple senders: Adding a second SPF record for a new tool instead of merging → PermError.

Fix order of operations

1. Consolidate to one SPF record; merge mechanisms.
2. Add include:sendgrid.net and other required includes.
3. Reduce lookups: replace include cascades or flatten (carefully).
4. Publish; wait for TTL; re-test with dig and MXToolbox.
5. Send test messages; confirm spf=pass and dmarc=pass in headers.

How AutoSPF helps

• AutoSPF continuously lint-checks your SPF, collapses overlapping mechanisms, and safely flattens includes to keep you under 10 lookups—without breaking when SendGrid rotates IPs.
• It ships a resolver that expands includes exactly as receivers do, so you see PermErrors before your customers do.

Designing SPF when SendGrid is one of many senders (O365, Google Workspace, Mailchimp)

Safe consolidation pattern

• Single record, merged mechanisms: v=spf1 include:sendgrid.net include:spf.protection.outlook.com include:_spf.google.com include:servers.mcsv.net -all
• Consider subdomain delegation:
  • Transactional: mail.example.com → SendGrid-centric SPF.
  • Corporate mail: example.com → O365/Google Workspace.
  • Marketing: news.example.com → marketing platform.

Avoiding the 10-lookup limit

• Flatten only through automation; manual flattening goes stale as providers change IPs.
• Prefer native includes over unnecessary a/mx mechanisms.
• Use redirect= only if you want a single authoritative policy shared across labels.

Forwarding and lists

• Expect SPF to break downstream; rely on DKIM for DMARC pass.
• Ensure SendGrid DKIM aligns with your From domain; do not rotate From to third-party domains.
• If you control forwarders, implement SRS to preserve SPF.

How AutoSPF helps

• AutoSPF builds per-subdomain SPF tailored to each use case, keeps you under lookup limits with dynamic flattening, and warns when adding a new platform would exceed limits.
• It offers curated sender templates (SendGrid, O365, Google, Mailchimp, Zendesk, etc.) to prevent typos and misincludes.

After you fix SendGrid SPF: monitoring to confirm recovery

What to watch

• SendGrid Deliverability Dashboard: Bounce/deferral codes (5.7.x auth failures, 4.7.x throttles), blocklist alerts, and inbox placement trends if enabled.
• DMARC aggregate (RUA) and forensic (RUF) reports: Confirm spf=pass and alignment; watch for sources still failing.
• Header sampling: Spot-check Authentication-Results across Gmail, Outlook, Yahoo.
• Complaint rates: Keep <0.1% at Yahoo/AOL; Microsoft SNDS insights for IP reputation.

Expected recovery timelines (AutoSPF case studies)

• B2B SaaS, 1.2M/mo via SendGrid + O365:
  • Pre-fix: Gmail inbox 61%, MSFT Junk 38%.
  • 48h post-fix: SPF pass 96%+, Gmail inbox 82%.
  • Day 7: Gmail 91%, MSFT Junk 9%.
• Ecommerce, 3.5M/mo via SendGrid + Mailchimp:
  • Pre-fix: Yahoo deferrals 22% (SPF PermError from 13 lookups).
  • 72h post-flatten with AutoSPF: deferrals <3%, DMARC pass >98%.

How AutoSPF helps

• AutoSPF ingests DMARC RUA data, correlates with provider-specific bounce codes, and alerts on regression.
• It verifies SPF/DKIM/DMARC on live mail streams, not just DNS, so you can prove impact and time-to-recover to stakeholders.

FAQ

Do I still need SPF if SendGrid DKIM passes?

Yes. DKIM passing is great, but DMARC requires either SPF or DKIM to pass with alignment. If forwarding breaks SPF or a DKIM key rotates incorrectly, having both authenticated and aligned provides redundancy and higher trust with receivers. AutoSPF ensures SPF is always correct even as your sending landscape changes.

Should I use ~all or -all with SendGrid?

• Use ~all during migration to avoid sudden rejects while you validate all senders.
• Move to -all once you’re confident your SPF covers all sources; this strengthens protection and improves receiver confidence. AutoSPF can stage this change, monitor impact, and auto-revert if issues appear.

Where should I publish the SPF record if SendGrid uses a custom Return-Path?

Publish SPF on the domain you use as your envelope-from (MAIL FROM). If you’re using a SendGrid-provided bounce subdomain via CNAME, SPF will evaluate there; also ensure the From domain has either aligned SPF (by using a matching envelope-from) or aligned DKIM for DMARC. AutoSPF checks both labels and flags misalignment.

What if I already have an SPF record for Office 365 or Google Workspace?

Merge—do not add a second SPF. Example: v=spf1 include:sendgrid.net include:spf.protection.outlook.com -all AutoSPF merges these safely and keeps lookup counts below 10.

How do I know if I’ve exceeded the 10 DNS lookup limit?

Run your domain through an SPF checker (MXToolbox, dmarcian) or AutoSPF’s resolver. If you’re at risk, AutoSPF will auto-flatten includes while preserving SendGrid authorization.

Conclusion: Protect and optimize your SendGrid deliverability with AutoSPF

A missing or misconfigured SendGrid SPF record immediately weakens authentication, breaks DMARC alignment, and triggers more spam placement, throttles, and outright rejects across Gmail, Microsoft, and Yahoo. The fix is straightforward—publish a single, consolidated SPF that includes include:sendgrid.net, ensure alignment, stay under the 10-lookup limit, and verify on live traffic—but operationally, maintaining this at scale is error-prone.

AutoSPF makes SendGrid SPF simple and resilient:

• Generates a single, compliant SPF that includes SendGrid plus your other platforms.
• Prevents common failures (multiple records, lookup overruns, typos) with continuous linting and dynamic flattening.
• Verifies DMARC alignment across From and envelope-from, including SendGrid’s bounce configuration.
• Monitors outcomes via DMARC reports and provider-specific telemetry, alerting you before reputation suffers.

If SendGrid powers any part of your mail, let AutoSPF own the SPF layer so your messages authenticate cleanly, align for DMARC, and land where they should: the inbox.