Book early and save: Yes (on these trains)
Online bookings usually open: up to 6 months ahead of the travel date - but this period of time is shorter when looking up journeys in August to October.
There are 2 x train services between Frankfurt (Main) and Heidelberg:
(1) These faster trains on which limited numbers of discounted tickets 'Sparpreis' are placed on sale, so when they're still available they can be the cheapest option on this route
(2) Other slower Regio trains; and when the discounted tickets for these express trains have sold out they're the cheapest option - so if you will be booking at the station just before boarding, they will be cheaper.
A choice of tickets
Four types of tickets are available on these express
Two types of discounted tickets, which will be cheaper the further ahead you book - Sparpreis Europa and Super Sparpreis Europa
Two types of non-discounted ticket - Flexpreis Europa and Flexpreis Plus Europa.
A key difference between these types of tickets is refunds:
- Super Sparpreis tickets are cheapest, but they can't be refunded at all.
- Sparpreis tickets can be refunded for a fee, but the refund will be in the form of travel vouchers to be used for alternative / future journeys.
- Flexpreis Europa and Flexpreis Plus Europa tickets can be refunded at no additional charge.
The other key difference is that both types of Sparpreis tickets are only valid on the specific departures selected when booking, but both types of Flexpreis tickets live up to their name, as they can be used on any departure on your travel date.
Note that none of the tickets can be exchanged to a different departure.
There's no need for this to be available for Flexpreis Europa tickets, as they aren't train departure specific.
If you book a Sparpreis Europa ticket and want to travel by a different departure you can refund it and then use the travel voucher towards the cost of the new booking.
Super Sparpreis Europa tickets can't be exchanged or refunded.
The Sparpreis, Flexpreis and Flexpreis Plus tickets also include 'City tickets', which can be used on public transport between locations in Frankfurt /Heidelberg and the stations.
Seat reservations
Seat reservations are optional on this route - take note if you will be using a rail pass.
They cost €4.90 when travelling in 2nd Class and €5.90 when travelling in 1st class.
Though they are included within the cost of booking 1st class Flexpreis tickets and both 1st and 2nd class Flexpreis Plus tickets.
Specific seats can be selected from seating plans - you don't have to accept the seat(s) that you will be automatically offered.
When booking Super Sparpreis, Sparpreis and 2nd class Flexpreis tickets, you have the option of purchasing seat reservations later.
It can be worth re-looking up a journey a week or two ahead of travel, because the DB website will indicate how busy a departure will be.
Booking on the DB website
You can find these direct IC trains more easily by making a proactive selection of 'Direct Trains Only'.
Or to see all the combinations of trains and journey options, some of which may be cheaper, take off the 'fastest connections' default.
Trains departing at different times can be cheaper than others leaving on the same day, so if you can be flexible with your departure time use the 'best prices' tool - at the top right on the list of journey options.