Regio (Germany)

The trains used on Regio services come in many shapes and sizes, as they fulfil different functions across the German rail network.

Some are double deck, others are single deck, some are very new, while others offer a retro travelling experience.

Regio train SERVICES can be broadly divided into four categories:

(1) Those that follow the routes of IC and ICE express trains, but stop at stations (including some airport/flughafen stations) that IC/ICE trains skip - so are slower than the express trains.

(2) Trains that link multiple towns in built up areas, on routes that usually aren’t taken by the IC or ICE trains.

(3) Semi-fast cross country trains in more rural areas.

These three faster services are categorised as RE 'Regional Express' trains and it can be worth looking out for these services, as they are quicker, but cost the same price as the slower Regio services - when both are an option.
The Regio trains that use double deck coaches are most often found on these three types of service.

(4 ‘Local’ trains OUTSIDE* of the major cities which call at every station - so rural branch line trains fall into this category.
These slower trains are designated as RB services on timetables. RB = 'RegionalBahn'.
*=the local stopping trains in the major cities are the S-Bahn services.

So something to watch out for is that on certain routes some Regio trains, (the RE trains) can be faster than others because they skip stations, while the slower RB trains will be calling at every station.
As a result it can be worth checking the arrival times of Regio trains on the paper departure sheets.
An RE train that leaves later than an RB train, can actually reach its final destination sooner.

What virtually* all Regio trains have in common is that seats can’t be reserved and that tickets aren’t discounted.

As a result tickets for journeys by Regio trains aren't usually available online.
*some Regio services/routes to/from Munchen are the exception.

What's particularly good to know is that if you book a ticket at the station for a journey by Regio trains, you can't then use it to travel by IC trains or ICE trains,

Non-folding bikes can generally be taken on board these trains, but specific terms and conditions such as, bikes being restricted at certain times of day (rush hours) and whether bike tickets are required, are dependent on the region in which you will be travelling.
The specific terms can also include only needing to purchase a bike ticket during rush hours, or bike tickets being valid for a day’s travel and not just on specific departures.

So it’s worth clicking on the links to the specific regional information on this page on the DB website– using Google Translate if need be.

Though what’s universal when taking bike on to any Regio train service is that bike spaces can’t be reserved in advance, so you cannot ever be 100% certain that space will be available on the train that you have boarded.
If it’s not, then it’s likely that the conductor will ask you to leave the train.