Why your bounce rate is over 3% and how to fix the list
The five usual causes of bounced cold emails, how to tell which one you have, and a safe routine for new lists.
A bounce is an email that can't be delivered. A few are normal. Many people who send cold email treat 3% as the point to stop and check the list. Some email services start reviewing accounts at about 5% and can pause them closer to 10%.
Bounces matter because mailbox providers watch them. A high rate teaches them to treat your messages as suspect, and that hurts the emails that were fine.
Five usual causes
| Cause | How it shows up | Fix |
|---|---|---|
| Old data | Bounces rise the older the list is | Use fresher data and re-check lists you've kept for months |
| Guessed addresses | Many bounces at the same company | Never guess firstname@ patterns |
| Catch-all domains | The server accepts everything, so a checker can't confirm the person exists | Send small batches and watch for delayed bounces |
| Mixed sources | One imported list bounces far more than the rest | Remove that source or re-check it |
| Typos and merges | Odd characters, missing dots | Clean the sheet before you send |
Work out which one you have
Sort your bounces by list, by company and by date. The pattern tells you the cause.
- All from one list. The data is the problem. Replace or re-check it.
- Clustered at a few companies. Probably catch-all servers or a company that closed.
- Spread across every list. Look at your sending setup, not the data.
A safe routine for every new list
- Send the first 100 to 200 emails only.
- Wait a day and count the bounces.
- Over 3%? Stop, find the pattern, and fix it before you send more.
- Remove every bounced address from all future lists.
Tip: Keep a column called status in your sheet and mark bounces. It becomes your suppression list.
What ContactYard does about it
Every contact in your search results already has a work email on file, and ContactYard only charges when it finds one. When you enrich a file, each row also shows an email verification date so you can see how recent the check was.
No list is perfect, and people change jobs every week. That's why the routine above still applies. Start small, read the bounce rate, then scale.
What to do next
Clean the list first, then send: clean a list before you send.
Keep reading
How to clean a list before you send: role inboxes, competitors and wrong titles
A short checklist to remove the contacts that waste sends or hurt your reputation, before you email anyone.
When to email the same list again, and what to change
Most people don't remember your first email. Here is when to contact the same market again and how to keep it fresh.
How to measure contact data quality with your own test
Run the same sample through any source, compare what you get and decide with numbers instead of promises.