Why do passport number change everytime it is renewed? why cant the same number be retained?

Question

Why do passport number change everytime it is renewed? why cant the same number be retained?

Answer 1

Its because they want to keep track of all the passports they issue. If you lose a passport, or its stolen, they want to be able to identify that particular document, and raise an alert if someone is illegally using it.

If the number was the same for different documents they couldn't track them.

Answer 2

The number is tied to that particular document, not any one person.

If a passport is lost or stolen, then they can use that specific number to try and find it.

If the same number was retained, it would be impossible to pinpoint one specific passport document, as that person would have had numerous passports.

Dual-nationality makes it more complicated: how could a person have passports from different countries which had the same identifying number?

Answer 3

Depends which country you are from and you also need to check this with the Immigration & Checkpoints Authority.. Or if you are in the US, its called Homeland Security Department, right?

Answer 4

Why do you care? What difference does it make to you whether it changes or stays the same (did you want to get a tattoo of your passport number).