Do I need to store IP addresses for an anonymous forum in the US?

An anonymous forum can attract serious abuse, including attempts to exchange stolen data or illegal material. That doesn’t automatically mean you must keep IP logs, but you should have moderation, reporting, takedown, and content-preservation procedures. Don’t promise complete anonymity unless you understand what your hosting, analytics, CDN, and security services record.

Think carefully about your retention and incident-response policies. A hash may help detect repeat abuse, but it usually won’t let you identify someone later if you receive a subpoena. Some providers also have their own logging or abuse-report requirements, so check those terms rather than assuming you control every layer of storage.

Hashing an IP address doesn’t necessarily make it anonymous. A predictable or unsalted hash can often be reversed with a lookup table, and even a properly salted hash can still let you link multiple posts to the same visitor. If you don’t need IP-based abuse controls, collecting nothing is usually more privacy-preserving than collecting a transformed version.

In the US, there generally isn’t one blanket federal rule requiring every anonymous forum to log raw IP addresses. Your obligations can depend on the type of content, your service providers, and any specific legal requests you receive. Consult a lawyer who handles privacy and online-platform law before launching, and make sure your privacy policy accurately describes what you do and don’t collect.