Driving on the motorway without slowing down or stopping to pay tolls is now possible thanks to "free-flow" tolling—also known as barrier-free tolling. Already in operation on the A13 and A14 motorways (the Paris-Normandy route), this system radically transforms the driving experience by combining smooth traffic flow, safety, and modernity. How does it work? How do you pay the toll within the 72-hour window? What equipment is required? In this article, we take a detailed look at how free-flow tolling works, the benefits of electronic toll collection, and simple ways to pay for your journey with complete peace of mind.
What is free-flow tolling?
Free-flow tolling is an automated payment system that allows vehicles to travel on the highway without stopping at toll barriers. Gantry cranes equipped with sensors and cameras detect and identify moving vehicles, automatically calculating the amount due based on the distance traveled.
How does free-flow tolling work?
Free-flow tolling is based on a simple principle: the automatic detection of each vehicle as it travels on the highway without stopping or even slowing down, in order to assign it the toll due.
The gantries above the traffic lanes are equipped with devices that determine the vehicle category (cars, trucks, etc.) based on its size and the number of axles. These sensors cover all lanes of the highway, including the emergency lane. They detect the vehicle's position on the road and its direction of travel, regardless of traffic or weather conditions. The system accepts the Liber-t electronic toll tag in vehicles equipped with one, provided it is correctly affixed to the windshield.
The gantries installed above the traffic lanes are equipped with advanced technologies:
- High-resolution cameras: read license plates.
- Classification sensors: determine the vehicle category (car, truck, etc.).
- Communication systems: interact with the toll collection tags.
These devices operate regardless of weather or traffic conditions, ensuring reliable and continuous detection.
Regulatory signage
Free-flow tolling is identified by specific signage introduced by the decree of March 18, 2024. As you approach an affected section, a round blue sign displays the words "PÉAGE" (Toll) and "Flux libre" (Free-flow); this signals that you are entering a barrier-free toll zone. More than 200 such signs have been installed along the Paris-Normandy route (A13-A14). The signs also indicate the available payment methods. It is important to note that you have 72 hours after passing through to pay your toll.
How to use the electronic toll collection badge when passing under free-flow toll plazas?
The electronic toll tag, such as the Liber-t, facilitates passage through free-flow toll plazas:
- Installation: Attached to the windshield, usually behind the rearview mirror, in the designated area.
- Automatic detection: The tag is detected when passing under the gantries, allowing for automatic debiting of the toll due.
- Benefits: time savings, centralized monthly billing, automatic passage without user intervention—ideal for regular trips on the A13 and A14. Access to additional services such as partner car parks.
It is essential to ensure that the badge is correctly positioned and in good working order to avoid any detection errors.
Good to know:
What payment solutions are available?
For users without an electronic toll tag, several payment options are available:
- Online payment: on the website sanef.com, by entering your vehicle registration number.
- Physical payment points: at tobacconists or newsagents partnering with the Nirio network, in cash or by bank card.
- Payment terminals: only on the A4 at the Boulay free-flow toll plaza, accepting various payment methods.
Payment must be made within 72 hours of the visit, otherwise penalties will apply.
What happens in the event of non-payment?
Failure to pay the toll constitutes a traffic violation (Article R419-2). If the toll is not paid within 72 hours, the following applies:
- Within 2 months: upon receipt of the payment notice, you must pay the toll plus a €90 surcharge (reduced to €10 if payment is made within 15 days of receiving the notice).
- After 2 months: the case is referred to the police court. The fine can reach €375.
Beware of SMS scams
Fraudsters are taking advantage of the rollout of free-flow tolling to send fake text messages requesting urgent payment. Sanef never contacts you via SMS to request toll payment. Payment can only be made:
- on the official website sanef.com
- at a tobacconist in the Nirio network
- via your electronic toll collection subscription
If you receive an SMS asking you to pay a toll by clicking a link, do not click it and report it at cybermalveillance.gouv.fr.
What are the advantages of free-flow tolling?
The free-flow toll system offers numerous benefits:
- Traffic fluidity: reduced congestion at toll points. On the Paris-Normandy route, up to 120,000 vehicles per day benefit from smoother traffic flow.
- Time savings: no need to stop, resulting in faster journeys. Up to 30 minutes saved on a 2.5-hour trip during peak traffic periods (Sanef estimate).
- Increased safety: lower risk of accidents near toll areas. Removing physical barriers eliminates the risk of collisions within the toll zone.
- Fuel savings and CO2 reduction: 9.5 million liters of fuel saved annually on the Paris-Normandy route (source: Transport Regulatory Authority, July 29, 2021).
- Reduction of land footprint: 28 hectares of freed-up space will be returned to nature once the traditional toll infrastructure on the Paris-Normandy route is dismantled.
Which motorways in France use free-flow tolling?
Free-flow tolling is already operational on several sections of the French motorway network. Here is the complete list of the motorways involved:
| Motorway | Operator | Section / Location | Launch Date |
| A4 – Boulay-Moselle (pilot site) | Sanef | Interchange No. 36, east of Metz (Moselle) | 2019 |
| A79 | ALIAE (Eiffage) | Montmarault (Allier) – Digoin (Saône-et-Loire), ~90 km | November 2022 |
| A14 | Sanef / SAPN | Montesson toll plaza + Chambourcy interchanges (Yvelines) | June 2024 |
| A13 | Sanef / SAPN | Full Paris–Caen route, 210 km, 12 toll sites | December 2024 |
Future motorway projects will also launch with a free-flow tolling system, in line with the State's aim to roll out this system widely. The A69 in the Tarn department and the A412 in Haute-Savoie are among the upcoming projects.
Frequently asked questions about free-flow tolling
How does free-flow tolling work?
Toll barriers are replaced by gantries equipped with cameras and sensors. These gantries automatically read your license plate and/or detect your electronic toll tag as you drive past, without requiring you to slow down or stop. The amount due is calculated based on your vehicle class and the journey taken.
Which French motorways use free-flow tolling in 2025?
In 2025, the free-flow motorways in France are the A13 and A14 (Paris-Normandy route, managed by Sanef/SAPN), the A79 in the Allier department (managed by ALIAE), and the Boulay-Moselle interchange (exit 36) on the A4 (managed by Sanef).
How do I pay a free-flow toll?
There are three options: (1) using a Liber-t electronic toll tag (automatic payment); (2) online at sanef.com within 72 hours of passing through; (3) at a tobacconist within the Nirio network, paying by cash or bank card within 72 hours.
What happens if I don't pay the free-flow toll?
If the toll is not paid within 72 hours of passing through, a €90 surcharge is applied (reduced to €10 if paid within 15 days of receiving the notice).
After two months, the file is forwarded to the police court, and the fine can reach €375.
Does my electronic toll tag work on free-flow motorways?
Yes, all Liber-t electronic toll tags (Bip&Go, etc.) work normally on free-flow motorways, provided the tag is correctly attached to the windscreen. No additional setup is required.
Does Sanef send text messages requesting payment for free-flow tolls?
No. Sanef never contacts customers via text message to request toll payments. If you receive such a message, it is a scam attempt (phishing). Payment can only be made via sanef.com, at a Nirio-affiliated tobacconist, or through an electronic toll subscription.