Understanding the 33/38 Rule for UK Campsites

If you’ve ever booked a campsite and seen "33/38 rule" on the page, you’re probably wondering what the numbers actually mean. In plain English, the rule tells you how many amps the site can supply and what plug type you’ll need. Knowing this before you pull up saves you from a tangled mess of adapters and a possible fine.

What the Numbers Stand For

"33" refers to the maximum amperage the site can provide – usually 33 amps. "38" is the standard British plug rating, meaning the site can safely handle a 13‑amp plug that’s common on most motorhomes and campervans. If a site lists "33/38", it means you can plug in a standard 13‑amp connector and draw up to 33 amps without overloading the circuit.

Why It Matters When You Arrive

Most motorhomes come with a 13‑amp socket that fits the UK plug. If you try to use a higher‑draw appliance like a powerful heater or an inverter that needs more than 13 amps, the site’s limit could trip the breaker. That leaves you in the dark and possibly paying a surcharge. Checking the rule helps you decide whether you need a separate power supply or a lower‑wattage setup.

Here’s a quick checklist to run through before you get to the pitch:

• Look at the campsite listing – does it mention 33/38 or another amp rating?
• Count the devices you plan to run at once (fridge, heater, shower pump, etc.).
• Add up their amp draws; stay well under the listed limit.
• Bring a compatible 13‑amp plug adapter if the site uses a different socket type.
• Ask the site staff if they have a higher‑capacity hook‑up available.

Most campsites in the UK stick to the 33‑amp standard, which is plenty for a typical motorhome set‑up. If you’re travelling with a larger vehicle that needs 45 amps, you’ll need a site that offers a higher rating – those are less common and usually cost extra.

Another point many campers miss is the length of the cable. A long, thin cable can cause voltage drop, making your appliances run inefficiently even if you stay within the amp limit. Keep the cable as short as practical and use a thick‑gauge lead for the best performance.

Finally, remember that the rule also influences how you park. Some sites require you to position the vehicle so the hook‑up point lines up with the power socket. Arriving early gives you flexibility, while a last‑minute booking might force you into a less‑ideal spot.

By understanding the 33/38 rule, you avoid surprise power cuts, keep your gear safe, and make the most of your campsite stay. Have you ever been caught off‑guard by a power issue on the road? Share your story in the comments – the community learns best from real experiences.