What Hitch Lock Do I Need for My Trailer? (Complete UK Guide)

Choosing the right hitch lock for your trailer isn’t always straightforward. With different hitch types, security levels and trailer uses, it’s important to get the right fit—not just for compatibility, but for proper protection.

Whether you’re towing a small domestic trailer or a high-value plant trailer, the type of hitch lock you choose can make a significant difference.

Step 1: Identify Your Hitch Type

Before anything else, check the hitch fitted to your trailer. Common types include:

  • Knott Avonride (common on Ifor Williams & Nugent trailers)
  • AL-KO hitch heads (AK270, AK301, AK351, AK3500 etc.)
  • Winterhoff hitch heads

The hitch model is usually stamped directly onto the coupling—this is the most reliable way to identify it.

Step 2: Understand the Types of Hitch Locks

There are two main categories:

1. Enclosed Hitch Locks (High Security) - (click here)

These completely cover the hitch head, preventing access to the mechanism.

  • Maximum theft protection
  • Often insurance-approved
  • Ideal for high-value trailers

2. Universal Hitch Locks - (click here)

These fit a wide range of couplings but don’t fully enclose the hitch.

  • More affordable
  • Quick and easy to fit
  • Suitable for lower-value trailers

Step 3: Match Security Level to Your Trailer

A simple way to decide:

  • Domestic / occasional use → Universal hitch lock
  • Regular use / moderate value → Mid-range protection
  • High-value / commercial use → Enclosed hitch lock

Common Mistake to Avoid

One of the biggest mistakes is choosing a hitch lock based on appearance rather than the actual hitch model.

For example, the AK351 and AK301 look very similar, but require different locks. Always check the stamped model number before buying.

Final Thoughts

The best hitch lock is one that:

  • Fits your hitch correctly
  • Matches the value of your trailer
  • Is easy enough that you’ll actually use it

If in doubt, it’s always better to go slightly higher in security—especially with trailer theft continuing to rise across the UK.