Towing Regulations Fully comprehensive insurance is essential and you will need to provide an up to date copy of your insurance schedule prior to collection of trailer. Cars must be fitted with a suitable tow-bar with single electrics. All drivers must be over 25 and under 75 and have at least two years driving experience. It is illegal to carry passengers in the trailer whilst the trailer is in transit. Speed and Lane Restrictions When towing, the speed limit is 60 mph on Motorways and Dual Carriage ways, 50 mph on other B roads. Use of an outside lane on a motorway is prohibited.