What is e-Roaming? How charging cards connect all networks
Roaming — the invisible glue between eMSP and CPO
Without roaming, every charging card would only work with its own operator. Only via the roaming platforms does the card gain access to thousands of foreign charging locations — and that is exactly where roaming costs are created and flow through the eMSP tariff into your electricity price.
1. What e-Roaming actually means
e-Roaming is the infrastructure via which a charging-card provider (eMSP) gains access to the charging stations of a foreign operator (CPO) — in such a way that the end user in the end receives a single bill from his own provider.
This does not work like a point-to-point telephone call: the data is exchanged over standardized protocols (at its core the OCPI (Open Charge Point Interface)). In the process, it is checked in real time whether the contract is valid, the charging is released, and at the end settled.
2. The big intermediaries: Hubject, Gireve & Charge League
An eMSP would theoretically negotiate contracts directly with each individual CPO (which it partly also does for its own network). In practice, the overwhelming majority of them use so-called roaming platforms, to connect thousands of stations through a single interface.
| Platform | Type & origin | Particularity / size |
|---|---|---|
| Hubject WAVE | Central roaming platform (WAVE) | Market leader in Europe. Connects > 1 million charging points. Nearly every large eMSP (ADAC, EnBW) uses Hubject as its backbone. |
| Gireve | Platform for large accounts & fleets | Focus on industrial settlement and large networks: many stations from public, semi-public and private operators. More widely spread in France, growing internationally. |
| Charge League | Internal roaming group (not a platform) | Exclusively bundles four large CPOs inside itself: Ionity, Fastned, Electra and Atlante. Drivers, however, still need an external eMSP to reach these stations — the League is therefore only the internal network of the operators. |
3. What happens technically (simplified)
- You insert the charging card or start via your app — your eMSP checks in real time via the roaming platform (e.g. WAVE) whether the target charging station is connected.
- The CPO's backend sends a reply: "Yes, I can supply the electricity." The charging session starts over OCPP at the station.
- At the end the charging station (via CPO backend → roaming platform) reports to the eMSP: "The customer has charged X kWh."
- The clearing house (e.g. e.clearing) settles the electricity between all affected companies in the background, before you receive your monthly bill from your eMSP.
4. Roaming costs: why foreign networks cost more
When charging in your own network, the eMSP pays the so-called wholesale price of the CPO. But when you plug your card into a foreign station, every level — CPO, roaming platform, eMSP — enters with its own margin. The result: a roaming surcharge. That is exactly why the same kWh costs more in a foreign network than in your own.
- Surcharge for foreign infrastructure: operators (CPO) demand a higher price for the use of their network — the eMSP passes this on to you in the tariff or absorbs it itself.
- Transaction fees: a few cents per charging session (often no longer individually visible in the tariff).
- Subscription flat rates: some eMSP tariffs include roaming throughout Europe — others only within a limited partner network.
The authentication and the settlement run in the background automatically between eMSP, platform and CPO — in the end you receive exactly one bill from your own eMSP.
What AFIR regulates here — and what it does not
Since April 2024 (EU-wide, via the AFIR regulation), no additional fees may be charged for cross-border roaming — a charging stop in France must not cost extra beyond the tariff. But the prices within the network itself (wholesale + surcharge) cannot be harmonized by AFIR: how much your eMSP charges for the use of a foreign network remains specific to the eMSP and CPO. That is why prices compared with charging in your own network are often opaque — a single regulator that would force all networks to one price does not exist in Europe (yet).
Roaming in the end: freedom vs. transparency
- Advantage: more freedom and comfort — one charging card, one contract, access to thousands of public charging points in Europe, without registering separately with every station operator.
- Disadvantage: the absence of unified regulation — the prices in a foreign network vary depending on the eMSP and CPO and are often not traceable in advance. Whoever avoids their own network pays the surcharge as a rule.
5. To read next
CPO & eMSP explained simply (Part 1) · What is OCPP? · What is an eMSP? · Next: What does the PSP and the clearing house do?
LadeGuide selects the right card for your roaming
Not all cards work equally well in every network. The app checks which charging card and which tariff cover the network along your route.
Learn moreSources
- National charging-infra service: glossary about roaming platforms.
- Bundesnetzagentur: AFIR obligations and e-Roaming without extra cost.
- Charge League documentation: association of the large operators (Ionity, Fastned, Electra, Atlante). Also see: chargeleague.com