Prompt
Why are my bounces suddenly spiking?
Latest observation
Oct 5, 2026
OpenAI APIWeb search: off
A sudden bounce spike usually means one of a few things changed, but the exact cause depends on what kind of “bounce” you mean.
If you mean email bounces
Common reasons:
- List quality dropped: older/invalid addresses, typos, role accounts, purchased lists
- Sender reputation issues: your IP/domain got flagged more aggressively
- Authentication problems: SPF, DKIM, or DMARC failing
- Mailbox provider changes: Gmail, Outlook, etc. tightened filtering or rate limits
- Volume pattern changed: sending a big blast after low volume can trigger blocks
- Content triggered filtering: suspicious links, attachments, spam-like wording
- Technical issues: bad From address, broken DNS, poor SMTP setup
What to check first:
- Bounce codes/messages (hard vs soft, and the SMTP error)
- Whether the spike is tied to one domain/provider
- Recent changes to list source, volume, content, or infrastructure
- SPF/DKIM/DMARC and sender reputation
- Suppression list growth and invalid-address rate
If you mean website bounce rate
Common reasons:
- Tracking/tag issue
- Traffic quality changed (ads, bots, low-intent campaigns)
- Landing page got slower or broke on mobile
- Messaging mismatch between ad/email and page
- UX changes made it harder to engage
- One-page content naturally causing “single-page sessions” to rise
What to check first:
- Whether analytics tracking changed
- Which traffic source/device saw the spike
- Page speed and error logs
- Recent site/design/content changes
- Session recordings or heatmaps
If you want, paste:
- email or web bounce
- the date/time of the spike
- any recent changes
- and a sample bounce error / analytics screenshot text
…and I can help narrow it down quickly.