Why Are My Emails Going to Spam?

Seven common causes, checked in order, starting with the one you can test for free right now.

Check your domain first: it's free

Our checker reads your public SPF, DKIM, DMARC and MX records and explains each in plain English. Nothing is stored.

Cause 1: missing or broken SPF

SPF is a DNS record that lists which servers may send email for your domain. Google says the SPF record "should include all email senders for your domain", and that mail from third-party senders that aren't included is more likely to be marked as spam. A domain must not have more than one SPF record (RFC 7208), and SPF allows at most 10 DNS-querying terms, so long chains of include: can break it.

Cause 2: no DKIM signature, or one for the wrong domain

DKIM adds a cryptographic signature that receivers check against a public key in your DNS. Google requires a DKIM key of 1024 bits or longer for mail to personal Gmail accounts and recommends 2048 bits. If your email tool signs with its domain instead of yours, DKIM can pass but still not count towards DMARC.

Cause 3: no DMARC record

DMARC tells receivers what to do with mail that fails SPF and DKIM, and lets you receive reports. Google and Yahoo both require DMARC for bulk senders; a policy of p=none is accepted as a start. Google also recommends that everyone sets up SPF, DKIM and DMARC.

Cause 4: a new or suddenly busy domain

Google advises increasing sending volume slowly and avoiding sudden spikes. A brand-new domain, or one that jumps from a few emails a day to thousands, is more likely to be rate-limited or filtered.

Cause 5: misleading content or links

Google's guidelines ask that subject lines, display names and links are accurate and not deceptive: no fake "Re:" subjects, no hidden HTML content, and links that are visible and easy to understand.

Cause 6: list problems

Sending to people who didn't sign up, or making it hard to unsubscribe, leads to spam reports. Google says to keep the spam rate reported in Postmaster Tools below 0.10% and never reach 0.30%; Yahoo asks all senders to stay below 0.3%, and asks bulk senders to honour unsubscribes within 2 days.

Cause 7: a shared IP with a poor reputation, or a blocklist

If your email provider uses shared IPs, other senders' behaviour can affect you. Google suggests checking that a shared IP isn't on a blocklist and using Postmaster Tools to check its reputation. This part is often outside your control, so ask your provider.

How to read "Show original" in Gmail

Send an email from your business address to a personal Gmail account.
Open it, click the three-dot menu and choose Show original.
Near the top, Gmail lists SPF, DKIM and DMARC with PASS or FAIL. You want all three to say PASS, and the domain shown for DKIM should be your own domain.

Prefer someone to fix it for you?

We set up or correct SPF, DKIM and DMARC through a fixed-scope Fiverr gig. You add the records yourself with our guide or grant delegated, revocable access to your DNS host. We never ask for passwords, and we can't guarantee inbox placement: that also depends on content, reputation and the receiver.

See the email-fix gig on Fiverr

Frequently asked questions

Will fixing SPF, DKIM and DMARC guarantee my emails reach the inbox?

No. Correct authentication removes one common cause of spam filtering and is required by Gmail and Yahoo for many senders, but each receiver also looks at content, sending reputation and recipient feedback. Nobody can guarantee inbox placement.

How long do DNS changes take to work?

Often minutes to a few hours, depending on your DNS host and the record's TTL. Re-run the free checker after you make a change.

Do I need DMARC if I only send a few emails?

Gmail requires DMARC only for senders of more than 5,000 messages a day to Gmail accounts, but Google recommends that all domains set up SPF, DKIM and DMARC. Starting with p=none does not block any mail.

Why do my invoices go to spam when my normal emails don't?

Invoices are usually sent by a different tool, such as your store, payment or accounting platform. If that tool isn't authorised in your SPF record or doesn't sign with DKIM for your domain, its mail can fail checks while your normal mailbox passes.

Is the email checker free, and does it store my domain?

Yes, it is free. It runs in your browser and reads only public DNS records via Cloudflare and Google DNS-over-HTTPS; nothing you type is stored by us.

Sources

Official documents we read on 24 Oct 2026. Requirements change, so check the source before acting.