The stamp goes on the front , in the upper right corner of the envelope’s address side.

Quick Scoop

  • Put the stamp on the front (the same side as the destination address), not the back.
  • Standard placement is the top right corner , leaving room below and to the left for the addresses.
  • If you accidentally put it elsewhere, most modern postal systems (like USPS) will usually still deliver it, but it might be delayed by sorting machines.

Simple mental picture

  • Imagine the envelope facing you.
  • Write the recipient’s address in the center-left area.
  • Your return address (if any) goes in the top left.
  • The stamp sits alone in that clear box of space in the top right.

If you’re ever unsure in another country, matching “stamp in the upper right on the address side” is the safest default.

TL;DR: For “which side does the stamp go on,” the best answer is: front of the envelope, upper right corner of the address side.

Information gathered from public forums or data available on the internet and portrayed here.