Why do my emails go to spam even though I have SPF and DKIM?

Authentication proves who you are, not that people want your mail. Volume, bounces and complaints still decide placement.

Can I fix a sender reputation that is already damaged?

Usually yes, slowly. Stop sending for a few days, clean the list, then restart at a low volume and raise it in steps. There is no instant reset.

Do spam trigger words matter?

Less than people think. Plain wording, few links and no attachments matter more than avoiding a list of words.

Does a separate domain for cold email help?

It can protect your main domain, but it adds setup and cost. It does not fix a bad list or too much volume.

Deliverability, diagnosed

Why do my emails go to spam?

Emails go to spam when mailbox providers see signs of bulk or unwanted mail: sudden volume from a new sender, many bounces, recipients who report you, missing authentication, or a message that looks mass-produced. Fix the cause that matches your situation, because no one can promise inbox placement.

Updated October 2026

What the filter is actually looking at

Gmail and the other big providers do not read your email and judge that it sounds salesy. They score the sender and the pattern. A sender they have never seen, sending a lot, to people who do not engage, with some addresses that do not exist, looks like spam whatever the words say.

So the causes below are about behavior and setup. The wording matters too, but it is rarely the first thing to fix.

The causes, most likely first

This order is a judgment from common problems in small senders, not a measured ranking. Check them in sequence.

Cause	How to check	Fix
1. New inbox, too much volume	Did you start above 20 to 30 a day?	Start with 10 to 15 and raise in steps
2. Bad list, many bounces	Do more than a few percent of a batch bounce?	Stop, clean the list, resume smaller
3. People report you	Do replies say "who are you?" or "stop"?	Narrow the list, honor opt-outs fast
4. No authentication	Does your domain have SPF, DKIM, DMARC?	Set all three in your mail admin
5. Looks like a mass email	Images, many links, heavy formatting?	Plain text, one link at most
6. No easy way out	No unsubscribe line?	Add a plain opt-out

1 and 2. Volume and bounces

A mailbox that has sent ten emails a week for two years can send more than one created yesterday. A new inbox that suddenly sends 300 emails looks like a hijacked account. Treat any new sending address as new and raise volume in steps over a few weeks.

Bounces are the other big signal. Mail to addresses that do not exist tells providers you built your list from somewhere questionable. If more than a few percent of a first batch bounce, pause. Watch your bounce rate on a small first batch.

Our guide to cold email bounce rate explains how to read the numbers.

3. Recipients report you

When a person clicks "report spam", that teaches the filter about you and about mail like yours. Google publishes sender guidelines for senders that push very large volume: keep reported spam well under 0.10% of messages and never reach 0.30%. A small sender is far below the volume those rules target, but the numbers show how little room there is. One complaint in 300 emails is already over the line.

Complaints come from people who had no reason to hear from you. The cure is a narrower list and a shorter, plainer email. Make leaving easy, and stop writing to anyone who replies, books or opts out. Rocketship sequences stop on their own in those cases.

4 to 6. Setup and format

If you send from a custom domain, set SPF, DKIM and DMARC. They tell receiving servers that you are allowed to send as that domain. Google Workspace walks you through all three.

Then the email itself. Skip attachments, big images and heavy formatting. Use one link at most, or none. Put a real postal address and a plain opt-out line at the bottom.

Rocketship turns on one-click unsubscribe by default and does not add an open-tracking pixel unless you ask for one.

How to test whether you are in spam

You cannot see the recipient's spam folder, so build a quick check. Send the same email to two or three Gmail addresses you control, from the same inbox, and look at where it lands. Then ask two friendly contacts at other companies to check. If it lands in spam for all of them, the cause is on your side. If one of five lands there, that is probably normal variation.

Also watch your own end: a sudden drop in replies, bounce notices, or a message in your admin console from Google. Fix one thing at a time so you know what worked.

Where Rocketship helps, and where it does not

Rocketship is one product that gets you customers, and the email step is built to keep sending behavior sensible. It sends from your own Gmail or Google Workspace account, not a shared pool, so your reputation is yours. Each new inbox ramps up gradually to a ceiling of 60 cold emails a day. Sequences stop when someone replies, books or unsubscribes, and one-click unsubscribe is on by default.

It works with Gmail and Google Workspace, and no tool can guarantee inbox placement. See plans and pricing. Launch is $24.99 a month, with a 7-day free trial, card required.