Is my passport too damaged to travel on?

What counts as damage rather than wear, the chip and the photo page as the two things that actually matter, and why the decision is never yours to make.

Difficulty: beginner
Time: 10 min
Read: 3 min
Safety: caution

Short answer

Wear to the cover and softened corners are normal. Damage means anything that affects the photo page, the machine-readable strip, the chip, the stitching or the page count: water staining, ink running, a detached or torn page, a delaminating photo page, or a chip that will not read. If any of those apply, replace it — a passport is only valid while it is legible and intact.

The line between an old passport and a damaged one is not written down as a checklist, because the test in practice is functional: can the document be read, verified and trusted. That makes it a judgement, and it is made by someone who has no incentive to give you the benefit of the doubt.

Safety

A passport judged damaged is treated as invalid, and the decision is made by whoever is looking at it — an airline agent, a border officer at either end — not by you. Being refused travel on a damaged passport is not an insured loss. If there is any doubt, replace it before the trip rather than argue at a desk.

Step by step

Look at the photo page under good light.It must be flat, fully bonded and completely legible. A page that has started to lift, bubble or peel at the laminate, or where the printing has faded or smudged, is the most common reason a passport is rejected.
Check the machine-readable zone.The two lines of characters at the bottom of the photo page have to scan. Creases, ink, scuffing or a worn strip across them stop the automated gates working, and a passport that cannot be read at an e-gate draws attention it does not need.
Test the chip.If you routinely fail at automatic gates and are sent to a desk, the chip may have failed. A chip is damaged by folding the book backwards, sitting on it, or a knock to the cover, and there is no way to repair it.
Count the pages and check the stitching.A missing or torn page invalidates the book, even a blank one, because page numbers are part of the document. Loose stitching or a page that has come away from the spine is damage, not wear.
Look for water damage.Wavy, stiffened pages and any running of ink are treated as damage. A passport through a washing machine is finished regardless of how readable it still looks.
If in any doubt, apply for a replacement.Replacement is an ordinary renewal application. Do it as soon as you have the doubt rather than close to travel, because processing takes as long as it takes.

Tips

Do not attempt a repair. Tape, glue or a re-stuck laminate turns a marginal passport into a definitely tampered-with one, which is a far worse position.
Some blank pages are needed for visas and entry stamps in countries that still use them. A book that is full is effectively unusable for those destinations even though it is undamaged.
Keep the passport out of the bottom of a bag. Most damage is mechanical, accumulated over years, and a rigid cover prevents nearly all of it.

Common mistakes

Assuming a previous successful trip proves it is fine — Different airlines and different borders apply different levels of scrutiny, and damage progresses. Getting away with it once tells you nothing about next time.
Leaving it until the week before travel — A damaged passport needs a full replacement application, not a quick fix, and the processing time is whatever it is on the day you apply.

Questions people ask

My child chewed the corner. Is that damage?

If it affects the photo page, the machine-readable zone or a page, yes. If it is purely the outer cover corner, it is usually treated as wear — but if it has gone through to the pages, replace it.

The passport works at some e-gates and not others.

That is a strong sign the chip or the machine-readable zone is marginal. It will keep getting worse. Replace it before it fails somewhere inconvenient.