We are arriving by Eurostar from London. We are catching a train at St. Lazare. We know about walking or the RER E. How long to clear French passport/customs when we get off the Eurostar??
You just walk off the train in Paris, no formalities.
https://www.seat61.com/trains-and-routes/london-to-paris-by-eurostar.htm#how-to-check-in
It doesn't take any time when you get off the Eurostar at Paris -- because you do both UK emigration and French immigration in London at St Pancras.
Therefore, when you arrive in Paris, you simply walk off the train.
It's very convenient that way !
Thank-You for the insight. Now I will find what to do for the 2-1/2 hours between trains. Thanks again
If you are walking, you will pass many a tempting patisserie or boulangerie on the way, an excellent way to take some of the time.