France

SNCF

SNCF is the biggest train network, with other European lines overlapping into the country on the borders.

General Advice: SNCF.com - Bike on Board

In 2019-2020 there were (and still are?) a lot of strikes. Google Maps won’t have a clue about the strikes, and will proudly tell you all about trains which don’t exist. To avoid getting caught out, use the OUI.SNCF website.

OUI.SNCF is amazing, and will help you book a trip where you can specifically mention that you have a bike. You say if it’s a foldable bike, in a bag, or fully assembled, and plot in the route you’d like to take. If there is a route, even if its slower or whatever, you’ll find it through this site.

Within the SNCF network there’s a bunch of different categories of trains.

TER (Regional Trains)

SNCF website mentions this:

When you take a TER regional train, your bicycle travels for free. Simply hang it up or place it in the designated area. Spaces in these areas are available on a first-come, first-served basis and cannot be booked.

What they don’t mention is that not all TER trains will have the carriage with the bike hooks on them. When trying to book from a kiosk machine, if you’ve said you have a bicycle it’ll tell you which trains have the carriage or not. The implication here is that you cannot get on trains when the bike hook carriage is not on the train, but I didn’t bother trying to storm the gates. I just waited for the next one.

Space permitting, bicycles can be carried free of charge.

You can use TERs with your bike even if the SNCF website does not have the little bike symbol.

TER is what you wanna try and go for if you’re not in a rush and do not want to pack up your bike.

TGV INOUI

For €10 you can book a space on a specific train when you book your ticket. no need to fold or disassemble your bike.

Ouigo

These are high-speed trains, with no designated spaced for bikes.

When you fold or disassemble your bike and store it in a carrying case, you can bring it aboard your Ouigo train for €5.

Right but it’s just going to be in the walkway and it could easily get kicked or belted with a suitcase. Try and avoid these unless you’re in a rush.

International

Then there’s Thalys, Eurostar, TGV Lyria.

Watch out for TGV Lyria, the rules are different to TGV INOUI. On TGV Lyria you’ll need to disassemble the bike and treat is as luggage.

You can take your bike, with the wheels removed and stored in a bag (maximum dimensions: 120 x 90 cm), free of charge and with no booking required in the TGV Lyria storage areas.

TVG Lyria Luggage rules.