This is the advice from the Caravan Club, dated 07/07/2009
Speed Limits France
We have now received confirmation from the legal department of Automobile Club de France regarding speed limits in France :
Motorway
Dual carriageway
Single carriageway
Vehicle towing a caravan/trailer where the vehicle has a gross train mass of under 3.5t - or a motorhome that has a gross vehicle weight under 3.5t*
autoroute 130
dual carraigeway 110
single carriageway 90
Motorhome which has a gross vehicle weight over 3.5t*
autoroute 110
dual carriageway 100
single carriageway 80
Vehicle towing a caravan/trailer where the vehicle has a gross train mass over 3.5t
autoroute 90
dual carriageway 90
single carriageway 80
*Motorhomes without a trailer, if the motorhome has a trailer then the speed limit will be based on the gross train mass.
Gross vehicle weight - the weight of the vehicle when fully loaded with luggage, and passengers etc to its maximum permitted capacity.
Gross train mass - This information can normally be found in your owner‟s manual, on a plate or sticker fitted to the vehicle or by contacting the manufacturer of your car. In general terms the GTM is the gross vehicle weight of your car plus its towing limit. (There are exceptions to this rule, if in any doubt please contact your car manufacturer.)
Example
Honda CR-V 2.2 i-CTDI SE
Gross vehicle weight - 2160kg
Towing limit - 2000kg
Gross train mass - 4160kg
If you tow any trailer/caravan behind this car you will need to tow at the lower speed limits regardless of how much your trailer weighs. If the Honda is towing a caravan weighing 1000kg (total weight of 3160kg) the lower speed limits will still apply, because the gross train mass is over 3500kg.
The French highway code stipulates that 80 and 90 stickers must be displayed by vehicles required to drive at the lower limits, however we have been contacted by various members who live in France advising us that this requirement is being ignored, and the French police are not interested in enforcing it, nevertheless it is legal requirement and the stickers can be purchased from