File Form I-90 with USCIS to replace a lost or stolen green card if you are in the U.S.

Report a lost U.S. visa to the local police and the U.S. Embassy or Consulate, then reapply for a new visa abroad with the police report

If you lose your green card abroad, get a boarding foil or transportation letter from the U.S. Embassy to re-enter the U.S. and then file for a replacement

Always carry copies of your lost documents, file a report immediately, and follow official replacement procedures to avoid legal and travel issues