Customs/Immigration Control with connections and checked luggage

Immigration (you) at the first Schengen entry (with EES likely) so Paris

Customs (your stuff) at your destination after collecting checked baggage, so Nice

We've done this connection; it's exactly as Nigel wrote. You do go through immigration at CDG but you and your luggage stay airside and you collect it in Nice.

The last time we flew that route was in 2020 during Covid, but I don't think the procedure was any different. We picked up our luggage at the Nice airport and walked out. BTW, 4 hours is a long connection. You should be able to do this in an hour or less.

4 hours is WAY WAY enough. People often make similar connections in half the time. You do not follow people arriving into Paris, you transfer airside following the yellow correspondence signage. You will not wait in the long line for Americans entering Paris and going through immigration. You will go through the process along the way to your gate with others who are transferring. Your luggage is automatically transferred and customs if any will be in Nice.

CDG is a complicated warren of terminals, so you might want to go online and see what your transfer will look like. But with that amount of time you don't need to be concerned.

Thanks all. That is good to know. Last time we flew into CDG (admittedly 8 years ago), immigration control was horrendous. There was no obvious line, and passengers were crowding in no particular order. It took over two hours for that activity alone. Perhaps that was the exception, but we were still advised to allow much more time than most airports. We will bring reading.

Connecting at CDG always takes me exactly 60 minutes, gate to gate. So, I am always comfortable with at least a 90 minute connection time (no less than that, and preferably a bit more).