United Kingdom Plug Adapter: Type G, 230 V for US Travelers

Where these numbers come from

The United Kingdom uses type G, the big three-pin plug. The pins are rectangular and sit in a triangle, and no US plug will go in without an adapter. Mains power is 230 V at 50 Hz, close to double the 120 V at 60 Hz that US devices expect. Most of what you pack, such as a phone charger or laptop brick, prints an input range of 100-240 V on the label, so it only needs the right prongs. The voltage difference matters mainly for heating and motor appliances.

Type G is unusual because the fuse lives inside the plug. A British plug holds a small cartridge fuse, often 3 A or 13 A, that protects the cord if something faults. A travel adapter with a built-in G plug leaves that fuse out of the picture for your device, so buy one that is fused or rated for at least the load you plug in. A 65 W laptop charger draws about 0.3 A at 230 V, far below any fuse rating. A 1,875 W US hair dryer on a converter is another matter.

Here is the arithmetic on that dryer. A 120 V heating element run at 230 V would draw about (230/120)^2 times its rated power, roughly 3.7 times, or around 6,900 W. That would fry it and could trip a 13 A fuse, which is good for about 3,000 W at 230 V. Converters that can carry 1,875 W are heavy and costly. Most hotels supply dryers, and a local one costs less than the converter.

UK sockets have shutters that only open when the earth pin, the longest of the three, pushes in. That blocks a two-pin trick some travelers try with loose adapters. It also means a cheap flat adapter that lacks a proper earth pin simply will not work in the wall. Pick an adapter made for type G with a solid earth pin. Bathrooms often have a shaver-only socket, and those are for low-power shavers and toothbrushes, not hair dryers.

If your route continues to Dublin, the same adapter works; see Ireland. Crossing the Channel to France needs a different adapter. Use the plug adapter finder to match each leg of a multi-country trip. Pack one fused G adapter, one multi-port USB charger, and leave 120 V-only appliances at home. Plug-and-voltage facts here are general travel information. Always read the rating label on your own device.

Sources

• BS 1363 plug and socket system
• Mains electricity by country (reference table)
• Power plugs and sockets: United Kingdom (US traveler view)
• AC power plugs and sockets (type reference)

Figures checked on September 30, 2026.

This page is general information, not legal, insurance or travel-agent advice. Fees, rules and limits change, so confirm the figures with the official sources listed above before you book or travel.