On an Interrail trip from Belgium, your Belgian plan works at no extra cost in every EU country and in Norway, but not automatically in Switzerland, Great Britain, Serbia, Bosnia and Herzegovina, Montenegro, North Macedonia or Turkey. Those seven countries are part of the 33 country Interrail network, yet they sit outside the EU roam like at home rules, so data there depends on your provider. This guide shows which countries on a typical Interrail route are covered, where the hidden costs are (border zones, ferries, the Eurostar), why your Interrail pass itself needs mobile data, and what to set up before you leave Belgium.
Where your Belgian plan works on an Interrail route
Covered by EU roaming rules | Not covered: check your plan before you go |
|---|---|
Every EU country on the Interrail network, from France and Germany to Croatia and Poland | Switzerland |
Norway (part of the European Economic Area) | Great Britain |
- | Serbia, Bosnia and Herzegovina, Montenegro, North Macedonia |
- | Turkey |
Inside the covered countries, you call, text and use data as you do at home, within the fair use limits of your plan. Outside them, every provider sets its own prices, and you may pay per megabyte, per day or through a separate travel bundle.
Switzerland: the country most routes cross
Switzerland sits in the middle of many classic Interrail routes, between Germany, France, Italy and Austria, so most travellers pass through it even when it is not a destination. Roaming in Switzerland is included in some Belgian plans, but not in all of them, and the scenic routes through the Alps are exactly where you will want maps, photos and messages. Check your plan before you board, or install an eSIM for Switzerland so your phone has data as soon as you cross the border.
The Eurostar to Great Britain
Great Britain is part of the Interrail network, and the Eurostar from Brussels takes you there in about two hours, with a passholder reservation. Since Brexit, roaming in the UK is no longer covered by EU rules, so whether your Belgian plan works there at no extra cost depends on your provider. The Eurostar offers free WiFi on board, which helps during the journey but not once you step out at St Pancras. A UK eSIM avoids that gap.
The Balkans and Turkey
Routes through Serbia, Bosnia and Herzegovina, Montenegro and North Macedonia are among the most rewarding on the network, and they are all outside the roam like at home area. The EU opened talks in 2026 to extend its roaming rules to the Western Balkans, but until an agreement is in force, treat every Balkan border as a new roaming zone. The same applies to Turkey, the easternmost country on the Interrail map. For a Balkan leg, an eSIM for Serbia is an easy place to start.
Three places where roaming costs catch you by surprise
Border zones
Near a border, your phone can connect to a foreign network before you have left the country. On the shores of Lake Geneva or around Basel, your phone may pick up a Swiss network while you are still in France or Germany, and charge Swiss rates.
Ferries
Many Interrail routes include ferries, for example between Italy and Greece or across the Baltic Sea. At sea, your phone can connect to an onboard maritime network, which is not covered by EU roaming rules and can be very expensive. Switch off data roaming as soon as you board.
Tunnels and mountains
Long tunnels and remote mountain valleys interrupt the signal on any network. Download what you need before a long stretch, so a lost connection never means a lost ticket.
Your Interrail pass needs data too
Most travellers now use the Interrail mobile pass in the Rail Planner app. The app works offline, but it needs to connect to the internet at least once every three days to keep your pass valid. On top of that, you will use data for seat reservations, night train updates on routes such as the European Sleeper or the night train to Vienna, maps in unfamiliar stations and messages home. Around 1 GB covers a week of light use.
Your checklist before you leave Belgium
Check which countries your plan covers. Look specifically for Switzerland and the UK.
Turn on data roaming for your Belgian SIM in the EU, and switch it off before a non EU border if your plan does not cover that country.
Download the Rail Planner app and your pass on WiFi at home.
Save offline maps for every city on your Interrail route.
Install a travel eSIM for the non EU countries on your route, so your Belgian number stays active for calls and texts.
One trip, many borders, one connection
An Interrail trip is built on freedom: you choose your route as you go, and your phone should follow without a zone chart to check at every border. Traditional telecom still treats each new country as a reason to charge more, while Firsty is built so your connection simply works, in more than 176 countries and with no surprise bill. Every connection Firsty sells also connects someone in Belgium who needs one, not as charity, but as how the business works. Things are moving, so keep an eye on what Firsty is building and discover more at Firsty.app.
FAQ
Does my Belgian phone plan work on an Interrail trip?
Your Belgian plan works at no extra cost in every EU country and in Norway, Iceland and Liechtenstein, thanks to the EU roam like at home rules. It is not automatically covered in Switzerland, Great Britain, Serbia, Bosnia and Herzegovina, Montenegro, North Macedonia or Turkey, which are all part of the Interrail network. Check your plan for those countries before you travel.
Does roaming work in Switzerland with a Belgian plan?
Switzerland is not part of the EU roaming rules, so it depends on your provider. Some Belgian plans include Switzerland and others charge extra. Check your plan before you cross the border, or use a travel eSIM for Switzerland.
Is roaming in the UK free with a Belgian plan?
Not automatically. Since Brexit, the UK is outside the EU roam like at home rules, so each Belgian provider sets its own UK rates. Some plans include the UK, others charge per day or per megabyte.
What are the rules for using an Interrail pass from Belgium?
The Interrail pass is for European residents and covers 33 countries. It does not give unlimited travel in your country of residence: as a Belgian resident, you get two journeys in Belgium, one to leave and one to return. Most high speed, international and night trains, including the Eurostar, also require a seat reservation at an extra cost.
How much does two weeks of interrailing cost?
The pass itself depends on duration, age and class, and Interrail regularly runs promotions. In September 2026, the standard price of a 15 day continuous Global Pass in second class was €357 for travellers aged 12 to 27, with higher prices for adults. Add seat reservations, accommodation, food and mobile data for countries outside the EU roaming area.
What is the difference between Interrail and Eurail?
Interrail and Eurail are the same rail pass network. Interrail is for residents of Europe, while Eurail is for travellers who live outside Europe. As a Belgian resident, you buy an Interrail pass.
Is there a free Interrail pass?
Yes, through DiscoverEU, a European Union programme that gives free travel passes to 18 year olds. Places are awarded through application rounds and a short quiz. The next round runs from 1 to 15 October 2026 for young people born in 2008, with travel between March 2027 and May 2028.
Do I need mobile data for the Interrail mobile pass?
Yes, but not constantly. The Rail Planner app works offline, but it needs to connect to the internet at least once every three days to keep your mobile pass valid. WiFi or mobile data both work.
