A postage stamp should be firmly attached, fully visible, and able to receive a cancellation mark.
Why tape should not cover a stamp
USPS mailing standards require postage to be affixed so it can be recognized and canceled. A transparent coating can change the surface, obscure part of the design, or prevent a normal cancellation mark. The problem is the tape covering the postage—not the mere presence of tape somewhere else on an envelope.
Overlapping stamps create a similar issue: a covered portion cannot reliably be counted as visible postage. Lay multiple stamps flat without overlap when combining values.
What to do if an unused stamp will not stick
- Do not tape over the stamp or coat it with glue.
- Keep the backing, packaging, and purchase record if available.
- Use a different intact, unused stamp when the letter must be mailed promptly.
- Ask the seller or a USPS retail counter about the defective stamp rather than guessing whether it will be accepted.
Do not remove a stamp from previously processed mail and reattach it. Used postage cannot be reused. The guide to stamp validity and expiration explains the difference between old unused postage and already-used postage.
Damaged, torn, or partly taped stamps
USPS must judge the condition of a specific piece. Mailing standards reject mutilated, defaced, or covered postage that cannot be properly recognized or canceled, and USPS guidance treats a stamp missing a substantial portion as unsuitable for use. A tiny edge defect and a heavily torn stamp are not the same situation, but the safe response is to replace uncertain postage or present the piece at a retail counter.
Do not try to reconstruct a stamp with tape. That can make the condition harder to evaluate and can resemble altered or reused postage.
Place the stamp correctly
Affix the stamp flat in the upper-right corner of the address side. Keep it clear of the return address, delivery address, envelope edge, clasps, and other stamps. See the illustrated stamp-placement guide when using several stamps or a nonstandard envelope.
Frequently asked questions
Can I put tape over just one edge of a stamp?
Avoid covering any part of the postage. Use an intact replacement or ask USPS to inspect the specific stamp.
Can I use tape near the stamp?
Tape elsewhere on the envelope is not the same as tape over the stamp, but keep the postage completely uncovered and the mailpiece securely prepared.
Can I glue a used stamp onto another envelope?
No. Postage that has already been used cannot be reused.
What if an unused stamp was torn while removing the backing?
Do not tape the pieces together. Use intact postage and ask the seller or USPS whether any remedy applies to the damaged unused stamp.
USPS sources and review note
- USPS DMM 604 — postage payment and invalid postage
- USPS Customer Support Ruling PS-281 — torn postage stamps
Reviewed in August 2026. Acceptance of a particular damaged or covered stamp requires inspection of the actual mailpiece.
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