Why Are My Emails Going to Spam?
7 Common Causes and How to Fix Each One

Published May 2, 2026 · 7 min read

You wrote the perfect email. Hit send. Nothing bounced — but your recipient never saw it. It landed in spam. Why are my emails going to spam? It's almost never one thing. Here are the 7 real reasons — and exactly how to fix each one.

1. You're Missing SPF, DKIM, or DMARC Records

This is the #1 reason emails go to spam. In 2024, Google and Yahoo made authentication mandatory for anyone sending more than 5,000 emails per day. Without these three DNS records, your emails look like forgeries to spam filters.

Fix: Use our free SPF/DKIM/DMARC setup guide to configure all three in under 10 minutes. Then verify with the email deliverability checker — you should see green checks across the board.

2. Your Domain Is on an Email Blacklist

Blacklists are databases of domains and IPs known to send spam. There are over 100 public blacklists — and being on even one major list (like Spamhaus or Barracuda) can silently send your emails to spam folders at every major provider.

You might be blacklisted without knowing it. Common triggers: a compromised mailbox that sent spam, a shared hosting IP with a bad neighbor, or a sudden spike in bounce rates.

Fix: Run a free email blacklist check across 100+ blacklists. If you're listed, each blacklist has a delisting procedure — usually a simple form. Most clear within 24-48 hours.

3. Your MX Records Are Misconfigured

MX records tell the world where to deliver email for your domain. If they're missing, pointing to a decommissioned server, or configured with wrong priorities, receiving servers can't verify your domain can receive email — and may junk your outbound messages as suspicious.

Even if you can send and receive, a misconfigured MX looks unprofessional to spam filters. Google Postmaster Tools explicitly flags domains with MX issues.

Fix: Check your MX records with the free MX record checker. You should see at least one valid MX entry with a reasonable priority value.

4. Your Email Content Triggers Spam Filters

This one hurts — your perfectly legitimate email might just look like spam. Common triggers:

Fix: Our free spam checker tool analyzes your email content against major spam filters and gives you a score. Aim for below 2.0 on the SpamAssassin scale.

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5. You Have Low Sender Reputation

Email providers like Gmail and Outlook track your sender reputation — a score based on your sending history. If too many recipients mark your emails as spam, delete them without opening, or simply never engage, your reputation drops fast.

New domains start with zero reputation. If you blast 10,000 cold emails from a domain registered last week, almost all of them will go to spam.

Fix: Warm up new domains slowly. Start with 50-100 emails/day to engaged recipients. Use a tool to test deliverability before campaigns. Monitor your reputation via Google Postmaster Tools (free).

6. Your SPF Record Has Too Many DNS Lookups

SPF has a hard limit: 10 DNS lookups. If you chain too many include: statements — especially nested includes from services that themselves include others — you exceed the limit and SPF returns a PermError. Result: your emails fail authentication and go to spam.

This is surprisingly common. A typical stack (Google Workspace + SendGrid + HubSpot + Salesforce) can easily hit 8-10 lookups without you realizing it.

Fix: Use the SPF/DKIM/DMARC guide to audit your SPF record. Consider flattening your SPF (manually resolving includes to IP ranges) or using a dedicated subdomain for marketing emails.

7. Your Emails Aren't Properly Authenticated for Forwarding

When someone forwards your email, or when it passes through a mailing list, the original SPF check breaks — the forwarding server isn't in your SPF record. Without additional protection, forwarded emails fail authentication.

The standard fix is DKIM + DMARC with p=quarantine or p=reject. DKIM survives forwarding because the signature is in the email headers, not tied to the sending IP. DMARC tells receivers: "trust DKIM even if SPF fails."

Fix: Configure DKIM first, then set up DMARC with p=quarantine (start there, move to p=reject after monitoring). Use the free DMARC setup guide — it takes 5 minutes.

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Quick Diagnostic Checklist

Still asking "why are my emails going to spam?" Run through these 7 checks in order:

  1. ✅ Does my domain have valid SPF, DKIM, and DMARC records?
  2. ✅ Am I listed on any email blacklists?
  3. ✅ Are my MX records correctly configured?
  4. ✅ Does my email content pass spam filter checks?
  5. ✅ Is my sender reputation healthy?
  6. ✅ Does my SPF record have fewer than 10 DNS lookups?
  7. ✅ Will my emails survive forwarding? (DKIM + DMARC)

Start with the free email deliverability checker — it runs checks 1-4 automatically in one click. From there, you'll know exactly what to fix.

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