Bartertown.com

For lost or damaged mail.
I just got this url from an USPS employee mailing.

https://www.usps.com/ship/file-domestic-claims.htm

Instuctions are all there. It's for domestic claims only. You have to go to the post office to file for international claims.

Please sticky this.

[Admin edit - Good idea. I think I shall - MM]

I filled one of these out recently. As it was a trade and I didn't have a receipt or invoice, all I could do was screen cap the retail value of the package, and screen cap the agreed trade form my messages here.

Has anyone had any luck with them?