What documents do I need if I am entering the USA from Canada and my USA passport has been mailed for renewal?

If I live in Canada and I am sending my USA passport for renewal by mail, what documentation can I use to prove I am a US citizen and have just sent my passport for renewal.

I would like to do this without incurring any additional expenses e.g. purchasing some other form of ID to cross the border in the interim. I don't need any rush documentation but want to be able to cross the border in case of any family emergencies or planned functions that I should be at. Thank You.

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Under the Western Hemisphere Travel Initiative (WHTI), U.S. citizens entering the the U.S. by air, land or sea from Canada must have a WHTI-approved travel document.

Entering the U.S. by Air

When entering the U.S. from Canada by plane you are required to present a U.S. passport, with these exceptions.

The only exceptions to this requirement are for:

* U.S. citizens on active duty with the U.S. Armed Forces, traveling with military ID and travel orders

* U.S. citizen merchant mariners traveling in conjunction with maritime business, with U.S. issued Merchant Mariner Document

* Travelers with a NEXUS card used at a NEXUS kiosk at Canadian Preclearance airports

* U.S. Lawful Permanent Residents with a Permanent Resident Card or other evidence of permanent residence status and required documentation; refugees and asylees with a Refugee Travel Document

Entering the U.S. by Land

If you are a U.S. citizen driving, taking a bus or train back from Canada into the U.S., you are required to present a U.S. passport, U.S. passport card, enhanced driver’s license (EDL) or Trusted Traveler Program card. Some travelers may be part of the WHTI Special Groups in which case travel document requirements may be different.

Traveling to the U.S. by Sea

Travelers taking a ferry or small boat back to the U.S. from Canada area must have a U.S. passport, U.S. passport card, enhanced driver’s license (EDL) or Trusted Traveler Program card. Some travelers may be part of the WHTI Special Groups in which case travel document requirements may be different.