Paris to Normandy Train Reservation Issues

I hope you priced out purchasing the tickets directly and the railpass came out cheaper. Many years ago a railpass was a real steal but these days it often is not.

As for the TER train, seat61 says

TERs are local regional trains, with affordable fixed-price open tickets and no advance-purchase discounts so you may as well just buy at the station on the day - these trains can never 'sell out'. There are no seat reservations, you just sit where you like.
https://www.seat61.com/train-travel-in-france.htm#TER

Once in Normandy (either Caen or Bayeux ) a car is helpful for visiting the region.

For June 23, regular tickets from St Lazare to Bayeux cost from 15€ to 42€ depending upon the train you take.

I cannot answer specifics about Eurail passes because I advise anyone against using them, they are expensive and seat available is often limited.

https://www.sncf-connect.com/

In your case it is pretty easy - TER trains don't require reservations. You can't find the price because there isn't one.

You are boarding at Gare St Lazare? That's the origination point for the train. If you are worried just get there a few minutes early and when the train is called go to that platform and hop on.

If more people get on than there are seats, they stand until some get off.

I hope that the rail passes save you money now that you have bought them.

Thanks for the replies so far. I did compare prices for the Eurail pass plus reservation fees to the cost of direct booking before I purchased the Eurail. I'll be visiting several countries and the pass does appear to save some money. The only leg of the trip that I've had trouble with is this Paris to Normandy one because I've found conflicting information about the need for (and cost of) reservations. If I am able to figure this out (with your help), my plan is to rent a car once in Bayeux.

There is no need for a reservation on that route.

This TER train to Normandy you can board with just a Pass. I use a Pass in Europe but definitely would not when going from Paris to Normandy, which I've done a number of times. Not worth using the Pass on a TER. I always used point to point tickets.

You will find a seat, even if not together. There are no seat reservations on this route. Seat reservations do not apply to TER trains.
If you encounter no seats available, you stand, as would anyone else.

my plan is to rent a car once in Bayeux.

many people find more rental options in Caen. It's where we rented our car.

I did compare prices for the Eurail pass plus reservation fees to the cost of direct booking before I purchased the Eurail.

Where?

I bring this up for others. If you use a site such as this: https://www.eurail.com/en, you will not see all the SNCF schedule, nor are you likely to see the discounted trains.

Those making a Eurail pass cost comparison should compare with sites such as https://www.sncf-connect.com/ or if you are redirected, use https://www.saveatrain.com/

For example, tickets from St Lazare to Bayeux cost as little as 10€ if purchased in advance. Purchasing tickets early and using these basic sites can save a great deal of money.

Thanks all. As for price comparing, the Paris Normandy leg of my journey is the least expensive one. I have several longer, more expensive legs in several countries. I compared the cost of the Eurail pass to the cost of point to point for my itinerary with SNCF, SBB.ch for switzerland, and trenitalia, in addition to Eurostar. One issue for me may have been that I didnt start booking my trip until two months prior. In the past, I have always booked Europe travel much more in advance. Perhaps if I had gotten an earlier start, I could have saved with point-to-point.

Now that I've bought the pass and my other tickets, my main concern here is that I'll be able to get the train to Normandy on the days I need it (using the Eurail pass if it helps me).

Contrary to what has been stated above, all "Nomad"-branded trains between Paris and Normandy now require reservations... it is a fairly recent development (since 2020, or maybe 2021 even), an unfortunate one at that!
Eurail cannot sell reservations for those trains run by the region, and SNCF stopped selling passholder reservations on their website a while back...
So, you'd have to physically go to a French train station to buy those reservations, which is quite the hassle.

Since you are renting a car in Normandy anyway, you are right to consider driving from Paris, it's not that long and you can stop at, say, Honfleur or Giverny on the way.