Do I need special paperwork for my car to cross into Canada at Niagara Falls?

Yes, yes you do. You need lots of 'special' paperwork, in fact.

The first things you'll need are a valid driver's licence, proof of insurance and vehicle registration. The next thing you'll need is a valid passport.

Those first three things are actually required in all US states, so they shouldn't be a surprise. The last thing, however, is specific to your country. Because you can't go home without it. You can enter Canada just fine with only a piece of government issued ID, but you can't get back home without the valid passport. Your country's rules, not mine.

Don't ask me what happens to Americans who try to come home without a valid US passport, because I don't know. Maybe you're sent to secondary interview while some overpaid CBP officer consults with another overpaid DHS officer, maybe you're asked to submit fingerprint / blood / urine samples to prove you really are who you say you are, or maybe you're forever exiled and have to start a new life in Puerto Rico or whatever. To tell the truth, I've never asked.

But trust me, you want to have that valid passport. It's easier than being exiled.

If you're crossing from Canada to the US you will need a pass port or a nexus license. They don't allow birth certificates or regular drivers licenses as ID any more, when you're going from Canada to the US. If you're bringing any one with you, they will also need a pass port. I live in Canada and have driven across the boarder to the US many times with my husband.

I used a pass port when crossing from the US back to Canada.

If you don't have a nexus license then bring your pass port. If you don't have one or you have to renew it, get it done asap. It takes 4-6 weeks to renew or get a new pass port, in Canada. Tell any one that's coming with you, that they will also need to bring a valid pass port.

You have to have a license, registration, and proof of insurance to drive in Canada.

You need a passport (or passport card), enhanced driver's license or equivalent travel document to cross a land border into Canada.

The usual stuff you would show a cop, including insurance valid in Canada.

Drivers license, registration, proof of insurance.

Identification (passports) for driver and passengers. Note that car insurance may or may not be honored.Check with your insurance co.

You would need a passport