Is a passport required to travel to Canada from California and back?

I need to visit my mother but i haven't reapplied for a passport. Is a California Drivers license okae? I was adopted legally in 1994....i need to leave in a couple of days...is it possible? Thanks everyone btw...

Canadians are about to need a passport to cross the border - go now or apply

If you are flying, then yes, you will need a passport.

If you are crossing the border by ground, then you'll likely be okay with a Driver's license, and some form of proof of American birth, like a birth certificate just in case. DO NOT RELY ON THIS THOUGH. Apply for the passport as soon as you're able, and get it expedited if you need to leave soon.

If you fly, yes it is required.
Depending on where she lives in Canada, you can usually fly to an airport near the border and then go across. I have done that in the past, fly to Washington and then go from there into Canada.
I was in Niagara Falls, NY last November and my children wanted to go to Niagara Falls, Canada and we were told that children have to have a birth certificate. I asked if there was any way and was told that they would let us cross, but could not promise that the U.S would let us back. It turned out not being a problem, that is evidently the law right now.

If you're flying you need a passport.

If you're driving, a birth certificate and driver's licence should do ...

I heard that there was a new law saying that US citizens needed a passport to enter Canada now. I don't know how easy and how quickly it is possible to get a passport. Sorry.

The requirements will soon change. You will need one to cross back from Canada next year, I believe, but if the trip is real soon you should be ok.

You used to be able to cross the borders only with an original birth certificate. However, due to terrorist concerns that has changed in the last couple of years. Yes you need a passport. Can you get one in a couple of days? Not very likely. You can pay almost double and they'll rush it but that changes the time from 6~8 weeks to a couple of weeks. Of course this is for a different state. California may be different but I'm pretty sure that it is federally mandated instead of state. Good luck though.

To cross from NY to Canada at this point in time you need only your US birth certificate and your driver's license. I would assume it is the same in other places. However, I believe you need one to fly. I have been told you can get back over without, say, the birth certificate, but it will take more time as you have to go in for questioning.

Just piling on here with the correct answer.

If you are flying, you need a passport.

If you are driving, you need your government ID (driver's license) and proof of citizenship (birth certificate).

This will change next year.