How to Fit a Tow Bar / Trailer Hitch: UK Guide
Whether you're towing a caravan, a trailer or a bike rack, a properly fitted tow bar is essential for safe and legal towing in the UK. Fitting one yourself is achievable for a confident DIYer, but there are real safety and legal considerations to get right. Here's what you need to know.
Types of tow bar
UK tow bars come in three main styles, and the right one depends on how often you'll tow and what you're towing.
- Fixed flange — the most common and versatile. A bolt-on ball that easily accepts bike racks and stabilisers. The ball stays in place permanently.
- Fixed swan neck — a neater, curved neck with a fixed ball. Tidy looking and great for caravans, though less flexible for some accessories.
- Detachable — the ball clips off completely when not in use, keeping the rear bumper clean. Ideal if you only tow occasionally and want to preserve the car's looks and parking sensors.
Browse the options in our trailer hitches range, and explore the wider towing products and winches selection for accessories.
What you'll need
- A type-approved tow bar kit matched to your exact make, model and year
- A trolley jack and axle stands
- Socket set and torque wrench
- The vehicle-specific wiring kit (7-pin or 13-pin)
- Trim removal tools and a multimeter
Legality and type approval
This is the part many people overlook. Any car first used on or after 1 August 1998 must have a type-approved (EC 94/20) tow bar designed specifically for that vehicle. Fitting a non-approved or generic bar can invalidate insurance and lead to a fine. Always buy a kit listed for your registration. The tow bar must also display a data plate stating its approval number, maximum nose weight and capacity.
Know your car's towing limits too — the maximum towing weight is in your handbook and on the VIN plate. Never exceed it. Your driving licence category also affects what you're allowed to tow, so check the rules on GOV.UK if you passed your test after 1997.
Fitting the tow bar: the basics
- Prepare: Park on level ground, chock the front wheels and safely raise the rear on axle stands. Remove the rear bumper and any trim as the instructions describe.
- Mount the bar: Offer the tow bar up to the chassis mounting points. Hand-tighten all bolts first so you can align everything, then torque to the manufacturer's figures — this is critical for safety.
- Cut-outs: Some bumpers need a cut-out for the neck or detachable receiver. Measure carefully and use the supplied template.
- Refit: Reattach the bumper and trim, and double-check every bolt is torqued correctly.
Wiring: 7-pin vs 13-pin
The electrics power the trailer's lights and, where fitted, fridge and charging circuits.
- 7-pin (12N) — handles basic lighting: indicators, brake, tail and fog lights. Fine for small trailers and bike racks.
- 13-pin — the modern standard, combining lighting with permanent live and charging feeds for caravans.
Many modern cars need a dedicated, vehicle-specific wiring kit that talks to the car's CAN bus system, enabling trailer detection and disabling rear parking sensors automatically. A universal kit can throw up warning lights, so buy the correct one. After wiring, test every function with the trailer connected before towing.
When to get it done professionally
If you're not comfortable working under the car, dealing with the CAN-bus wiring, or torquing structural bolts, have it fitted by a professional. A poorly fitted tow bar is a genuine danger to you and other road users. That said, plenty of capable owners fit their own with the right kit and care.
Can't find an approved tow bar or wiring kit for an older or unusual vehicle? Use our request-a-part service with your registration or part number and we'll help source the correct fitment.
Frequently asked questions
- Is it legal to fit my own tow bar in the UK?
- Yes, you can fit your own tow bar provided it's a type-approved kit for your specific vehicle and fitted correctly with bolts torqued to spec. Cars from August 1998 must use an EC 94/20 approved bar.
- Do I need 7-pin or 13-pin wiring?
- Use 7-pin for basic trailer and bike-rack lighting. Choose 13-pin for caravans needing permanent live and charging feeds. 13-pin is the current standard and adaptors are available.
- Will a tow bar affect my parking sensors?
- A correct vehicle-specific wiring kit communicates with the car and automatically disables the rear sensors when a trailer is connected, preventing false alerts. Universal kits often cannot do this.