International drivers permit

If you are stopped by a policeman you need it.

Yes, it is required, you may not have to present it at the time you rent the car, but will need if you get stopped. You will of course also need a valid Drivers license, actually, that is the purpose of the IDP, a notarized testament that the drivers license you have is valid. Likely, your passport will not be required.

It's cheap, easily obtained insurance against any problems if you should be stopped or in an accident. It assures the French authorities that that strange-looking card in English issued by your state is actually a valid driver's license.

Do we have to have an IDP

No.

Yes, it is required by France to have either an IDP OR to have a notarized translation of your local license into French. Either one needs to be accompanied by your valid local license. You will most likely not need it to rent a car, although you may depending on car rental agency. What you need it for is if you are stopped by police for any reason or get into an accident. If you don't have one of the options you are technically driving illegally and it could affect your car insurance if anything happens. Just get one, it's only $20-25 and a small price to pay.

EDIT: reminder - all drivers need to have an IDP.

boot,

As Nancy and others mentioned, you do need to have an IDP. Whether you're ever asked for it is not the issue. Some additional information.....

From the Embassy of France in Canada.....

If you come to France for a short visit (such as holidays), you can drive using your foreign licence. It must be valid and either written in French or accompanied by an official translation into French or an international licence."

From the Embassy of France in the U.S. .....

"You may drive with a valid U.S. driver’s license if it is accompanied by a notarized translation in French. It is strongly recommended that you carry an International Driving Permit. You must be 18 years of age or older to drive in France."

Given the small cost, it makes sense to have an IDP. Note that an IDP is not a license per se, so must be used in conjunction with your home D.L.

The wording for France is vague. They say if you are staying for less than 90 days, "It is generally recommended that you get an IDP". Other countries like Austria, Spain , Italy etc. say you must have one. The problem is, if you get stopped for a traffic violation or even worse have and accident how easy is it going to be for you to explain your US driver's license to a cop and even worse an angry motorist. If it's too much trouble to go to AAA to get one, go on line to the American Automobile Touring Alliance and get one. It' s just like insurance, only a foll would drive without it.

In 40,000 miles of driving in Europe the only time I was asked for and IDP was by the guy at the airport in Milan who made it real clear that without an IDP I would not get my lease car and I would be out every cent of the pre-paid lease.

An IDP is needed. It is not a notorized document claiming you have an official license. It is simply a translation of the information on your license. You must have your driver's license as well.

I don't plan to drive in Europe but I still carry an IDP just in case I change my mind. They are good for a year.

All the above comments are correct assuming you do not have a valid EU driver's licence. Should you have one, you would not need an IDP.

Maybe I'm silly but I find the idea of having an IDP fun! A little trinket for your international travels - truly a citizen of the world!

Have I ever needed it? Nope. But I've also not filed an insurance claim since I was a teenager but still pay my premium. Could you possibly get away with not having insurance, or even a valid license and registration? Possibly! You very well might go your entire life never getting pulled over, or in to an accident, or having a cop behind ya at a red light looking at the tags on your plate. But would you ever wanna risk it?

We will be traveling in France, renting and returning in Paris. Do we have to have an IDP if we have a passport and valid ID?

1) Only if you are driving a vehicle and your licence is from a non-EU country.
You can have an IDP or a certified translation of your licence. An IDP is the easier option.
You do not need an IDP if all your travelling is by train, bus, air or other methods.

2) "we have a passport and valid ID?" - your passport IS your valid ID. The only other valid ID is a National Identity Card issued by an EU country, do you have one of those?