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Why is my email going to spam? The fixes that actually work

InboxRadar grades your email deliverability free and emails you when it changes. Check your domain.

When your email lands in spam, it feels random. It is not. Mailbox providers like Gmail and Outlook decide where your message goes in a fraction of a second, and the biggest input they use is whether your domain is authenticated. Get authentication right and most deliverability problems disappear. Get it wrong and even a perfectly written email gets filtered.

Here are the real causes, in the order worth checking, and how to fix each one. You can see exactly which of these applies to your own domain in about three seconds with a free InboxRadar check.

1. You have no SPF record, or it is wrong

SPF (Sender Policy Framework) is a DNS record that lists which servers are allowed to send email as your domain. If it is missing, receivers cannot confirm your mail is really from you, and that alone pushes you toward spam. If it ends in +all, you have told the world that any server may send as you, which is worse than having none.

Fix: publish a single TXT record at your root domain, for example v=spf1 include:_spf.google.com ~all, using the includes your email provider gives you, and end it in ~all or -all. Never have more than one SPF record.

2. Your mail is not signed with DKIM

DKIM adds a cryptographic signature to every message, proving it was not altered in transit and that it really came from your domain. Unsigned mail is far more likely to be filtered.

Fix: turn on DKIM in your email provider (Google Workspace, Microsoft 365, your ESP) and publish the public key it gives you as a DNS record. Most providers have a one-click toggle plus a record to add.

3. You have no DMARC policy

DMARC ties SPF and DKIM together and tells receivers what to do with mail that fails. As of 2024, Gmail and Yahoo require a DMARC record for bulk senders, and increasingly route unauthenticated mail straight to spam. If you have no DMARC record, you are missing the single biggest modern deliverability signal. We cover the setup step by step in how to set up DMARC.

Fix: publish a TXT record at _dmarc.yourdomain starting with v=DMARC1; p=none; rua=mailto:you@yourdomain to monitor, then tighten the policy once your mail is passing.

4. Your sending domain or IP is on a blocklist

Less common, but if your domain was compromised or you sent to a bad list, you can land on a public blocklist. Authentication fixes come first, because they are what most filters actually weigh, but a listing is worth ruling out.

How to know which one is your problem

Rather than guess, check your domain. InboxRadar reads your live SPF, DKIM, DMARC and MX the way Gmail does, grades the result A to F, and tells you the exact record to fix, highest impact first. It is free and needs no login, and you can then have it watch your domain and email you the moment any of these breaks again.