Is it possible to permanently delete a file from a USB?

Solution
Pen drives are cheap to replace so if you want to be absolutely sure it's data can't be read, pull it apart and destroy the storage chips inside it with some strong pliers or electrical cable snips. Guaranteed 100% destroyed.

Supahos

Expert
Ambassador
A hammer is the only if IT HAS to be gone. Not pretty but all other methods could possibly still get tiny bits of data if the next person is good enough.

If it's not the end of the world. Use the format function in Windows... Then completely fill the drive with random crap, the reformat.