Junk Folder
Spam or junk foldering — accepted mail the provider hides from the primary experience.
Definition
Junk (spam) foldering is when accepted mail is filed away from the inbox because filters judge it unwanted or risky.
Why it matters
Connect spam-folder outcomes to reputation, complaints, traps, and content — not only missing authentication.
How it works
High complaint rates, spamtrap hits, poor engagement, and weak identity signals increase junk probability. Users marking mail as spam reinforce the signal.
Limitations
- Some providers discard mail without a visible junk copy.
Common misconceptions
- Junk placement is always caused by a missing SPF record.
How to verify
- Inspect Authentication-Results and spam diagnostic headers on samples.
- Correlate junk spikes with list quality and complaint changes.