Definitions and trigger criteria:
A transport is considered "exceptional" as soon as one of the standard criteria for size or weight is exceeded.
• Length: > 16.50 m — or even > 20 m depending on the category.
• Width: > 2.55 m
• Weight / GVW / GCW is significant, or the combination exceeds 44 tons (or depending on configuration).
• It may involve indivisible goods, special equipment, oversized materials, etc.
Depending on the characteristics, the transport can be classified into 1st, 2nd, or 3rd category of exceptional convoy.
---
Procedure based on the category:
• 1st category ("slightly out of standards")
• If the convoy slightly exceeds the standard limits but remains moderate, a simple prior declaration is sufficient.
• This declaration can be made online via the official "Mon transport exceptionnel" service.
• If online access is unavailable, the paper form (CERFA) can be filled out and sent by mail.
• Once the declaration is validated, the carrier receives an acknowledgment of authorization (often called APL — Local Scope Authorization). This acknowledgment allows circulation for a maximum duration of 3 years.
• 2nd or 3rd category (truly out-of-standard convoy)
• In these cases, an individual authorization is required.
• The request must be made via "Mon transport exceptionnel", or by paper form (CERFA n° 15625*03).
• The authorization must be sent to the prefecture of the departure department (or the entry department in France if the convoy comes from abroad).
• All necessary information must be included: description of the convoy (vehicle(s), trailer(s), load), dimensions and weight, proposed itinerary, dates and times, possibly a plan / diagram of the convoy, etc.
---
Where to submit the request:
• Through the online service "Mon transport exceptionnel" — standard procedure since 2023.
• By mail (CERFA form) to the prefecture of the relevant department (departure or entry).
---
Instructions & prior checks:
Before the transport, it is necessary to:
• Check the itinerary: via the official map portal for roads authorized for convoys (e.g., via Géoportail TE).
• Examine the heights, bridges, passages, potential construction sites, to ensure the convoy can pass.
• Adhere to legal deadlines: the authorization must cover the entire journey, and the request must often be made several days in advance.
---
Circulation rules after authorization:
Once the authorization is granted:
• The convoy must display the "EXCEPTIONAL CONVOY" signage.
• Reduced speed limits, depending on the road / type of convoy.
• Minimum distance between convoys, lighting, signage for overhangs, markings, possibly escort or guidance depending on the case.
• Certain restricted periods: from Saturday noon (or the day before a holiday) to Monday at 6 a.m., public holidays, or unfavorable weather conditions — unless an exemption is granted.
---
In practice — steps to follow:
1. Assess the convoy: dimensions, weight, type of load.
2. Determine the category (1st / 2nd / 3rd).
3. For category 1: make the prior declaration via "Mon transport exceptionnel" or the paper form.
4. For category 2 or 3: complete the individual authorization request, send it to the competent prefecture.
5. Attach all supporting documents (vehicle, trailer, load, itinerary, etc.).
6. Once the authorization is received: prepare the convoy (signage, coupling, itinerary, escort if necessary).
7. Travel while adhering to prescriptions, schedules, limitations, and keep the authorization available.