WASHINGTON (CNN) -- Beginning Monday, U.S. and Canadian citizens who want to cross the border will have to present a passport or a very limited number of other travel documents.
Here's a rundown of what will be accepted:
A U.S. passport, a travel document issued by the State Department. Passports cost $100 for people 16 and older and $85 for those under 16.
A U.S. Passport Card, a card valid for entry to the United States by land or sea from Canada, Mexico, the Caribbean or Bermuda. It is not valid for international air travel. The cards cost $45 for people 16 and older, $35 for those under age 16, and $20 if requested with a new or renewed passport.
A "trusted traveler" card. The cards -- NEXUS, SENTRI and FAST -- are issued to pre-approved frequent border crossers, allowing them to use dedicated lanes to expedite their crossings.
An Enhanced Driver's License. Four states currently issue the cards, which denote both the holder's identity and citizenship. Those states are Michigan, New York, Vermont and Washington.
More information can be found at www.GetYouHome.gov.
What about Mexico?
All Mexican nationals, including children, are currently required to present a passport with a nonimmigrant visa or other approved travel documents to cross the U.S. border. The new law will not change current practices.
However, it will affect U.S. residents attempting to re-enter the country at the southern border. They will face the same document requirements as at the northern border.