Travel · Thailand · Type A/B/C/O · 230V
Thailand: the socket that takes everything.
Thai wall plates are famously accommodating — hybrid openings that swallow flat American pins and round European ones from the same hole. That is convenient and quietly dangerous: every one carries 230V at 50Hz, and a plug fitting has never meant an appliance is safe.
Four plug standards, one hole
Thailand recognises Type A and Type B (US flat pins, with and without a ground), Type C (the European two-round-pin Europlug), and Type O — Thailand's own three-round-pin standard defined by TIS 166-2549, with a grounding pin. In practice a great many installed sockets are hybrids cut to accept several of these at once.
| Opening | Accepts | Grounded | What US travelers should know |
|---|---|---|---|
| Hybrid flat + round | Type A, B, C plugs | Sometimes | Your US charger goes in — at 230V |
| Type O (three round pins) | Thai grounded plugs | Yes | The current national standard |
| Type C only | Europlug two-pin | No | A Europe adapter covers it |
| Supply | 230V, 50Hz, on every one of the above | ||
The trap, stated plainly
Fit and safety are separate questions and Thailand answers only the first. A US 120V-only hair dryer slots into a hybrid socket with no resistance and then receives nearly twice its design voltage. Resistive heat scales with the square of voltage, so the element sees roughly 3.7 times its rated power. It fails within seconds, sometimes taking the room's breaker with it.
The device that decides is the label. 100–240V ~ 50/60Hz means dual-voltage and safe anywhere in Thailand. 120V or 110–125V alone means the device belongs in your suitcase, unplugged. Everything with a USB port on the end passes; almost everything with a heating element fails.
What to pack
Many US travelers need no adapter in Thailand at all. Packing one anyway is the difference between charging and not in the one room with a Type O socket only.
- Type O
Type C/O round-pin plug adapter
Turns your flat US pins into round ones for the sockets that will not take a flat blade.
- Output plug
- Round pin, Type C/O
- Function
- Shape only, no conversion
- Weight
- Pocketable
- Universal
EPICKA Universal Travel Adapter
Four output shapes and built-in USB — the pragmatic pick for a Bangkok–Singapore–Bali style itinerary.
- Plug types
- A, C, G, I
- USB
- 3× A, 1× C
- Fuse
- 8A, spare included
- 65W
Anker Nano II 65W GaN
One folding brick that runs a laptop and a phone off a single Thai socket, rated for the full 230V.
- Output
- 65W USB-C PD
- Input
- 100–240V
- Prongs
- Folding, Type A
Safe list and the short danger list
Safe on any Thai socket: phones, tablets, laptops, camera and GoPro chargers, drone batteries, e-readers, electric toothbrushes, cordless shavers, power banks, USB fans. All dual-voltage, all fine.
Leave home or replace with a dual-voltage model: hair dryers, flat irons, curling wands, travel kettles, corded shavers rated 120V, US-market humidifiers and any small appliance with an AC motor. Carrying a step-down converter for a hair dryer is possible but rarely worth the kilogram — see travel adapter vs converter for the honest comparison, and the converter guide for how to size one if you insist.
Onward legs change the shape but not the logic: Vietnam and Indonesia want round pins, Malaysia and Singapore want Type G. One universal adapter covers all four.
More guides
FAQ
Do I need an adapter for Thailand?
Often not — many Thai sockets are hybrids that accept US flat pins. Pack a round-pin adapter anyway, because Type O and Type C only sockets exist and a room with one of those leaves you with no way to charge.
Is it safe that my US plug fits a 230V Thai socket?
It is safe for dual-voltage devices, which is every USB charger and laptop supply sold in the US. It is not safe for 120V-only appliances, and the socket gives no warning either way.
What is a Type O plug?
Thailand's own three-round-pin standard, TIS 166-2549, which includes a grounding pin. It is the current national socket type and is not compatible with US flat pins.
Can I bring my hair dryer to Thailand?
Only if its label reads 100 to 240 volts. A 120V-only dryer on 230V receives roughly three and a half times its rated power and burns out almost immediately.