What this message means and why it happens
When anyone receives an email they don't want — whether it's cold outreach, a newsletter, a promotion, or anything else — they might click "Report spam" instead of just deleting it or unsubscribing. Gmail collects all of these reports across its entire user base.
Over time, Gmail builds a picture of what spam "looks like." This includes things like:
What the email contains (certain words/patterns, links, formatting)
How people have reacted to similar emails in the past
When your email matches that picture closely enough, Gmail flags it automatically and shows recipients the message: "It is similar to messages that were identified as spam in the past."
So it's not necessarily that your specific emails were reported — it could simply be that your emails share enough characteristics with other emails that were reported by other users at some point.
The core issue is sender reputation. Gmail is constantly scoring senders based on how recipients interact with their emails. If enough people ignore, delete, or report similar emails, that score drops, and Gmail starts treating your emails with more suspicion — even for recipients who might actually want to hear from you.
How to resolve
Stop sending emails with the affected email templates from your mailbox in the automation tool
Create a new template or rewrite the affected one (including the Subject)
Update the affected template in Folderly with a rewritten or a new version
Wait until the Folderly score is back to 90+
Update the affected template in the automation tool with the rewritten or a new version used in Step 3
Resume email campaigns for your mailbox in the automation tool
Best Practices
There is a list of best practices to follow to prevent this or similar issues in the future. The specific steps depend on whether you do email marketing or cold outreach. These are two different practices with different rules. Here you can find the difference between them.
Email marketing
Make it easy to opt out
Always tell recipients how to unsubscribe, even if it's just a simple line like "Let me know if you'd like to be removed from this list." People are often too busy or too embarrassed to ask, so they click "This is Spam" instead. Every time that happens, your reputation drops, and Gmail learns to send your messages straight to the spam folder. Letting them know it's okay to opt out encourages many of them to do the better thing and simply ask.
Watch your content
Skip the hype — no excessive exclamation marks or phrases like "You must read this" or "Don't miss out"
Don't use common spam words
Don't hide links behind tiny images or use white text on a white background
Avoid emails that are mostly images
Leave out emojis
Avoid long links and shortened links
Keep your signature simple — don't overload it with images, phone numbers, or GIFs
Keep your list clean
Remove bouncing addresses right away; repeatedly emailing dead accounts hurts your reputation
Validate your lead lists before sending
Get the technical setup right
Stay within your sending limits
Keep your DNS records clean and properly configured
Cold outreach
Set up a dedicated domain and mailbox
Use a domain reserved specifically for cold outreach — sending outreach from your main domain can damage its reputation
Make your mailbox name human, not generic — use anna@folderly.com rather than sales@folderly.com or info@folderly.com
Keep your DNS records properly configured
Mind your lead lists
Send only to valid mailboxes
Upload any "catch-all" mailboxes to a separate sequence
Keep your content plain
Use plain text, not HTML
Avoid spammy words like "$", "free", "trial", or "proposal"
Leave links, images, videos, GIFs, emojis, PDFs, attachments, and bold text out of the body, signature, and subject line
You can add any of those after a prospect replies — just not in the first message
Skip the unsubscribe link
For cold outreach, we don't recommend including an unsubscribe link
Have questions? Drop us a message in the chat.