Can I use a UK iPhone charger with my US iPhone in the UK, or do I need to use an adapter and my US charger?

If your US iPhone charger is an Apple product, it will happily charge your iPhone in the UK; an Apple charger can accept the higher voltage provided by electrical sockets in the UK. Some (perhaps most) aftermarket chargers will also do this.

The standard US power plug is differently-shaped than UK sockets. The simplest solution is a plug adapter, so that the two- or three-prong plug you use in the US can connect to the differently-shaped UK sockets. Because there are no electronics in a plug adapter (just a change in the physical presentation of the connectors), they're less expensive than buying a new charger.

Plug adapters look like this:

(image from Google)

A million different varieties of plug adapters are available all over the place: hardware stores, markets, airports, mail order. I have a paper bag of various adapters in my closet, and have used them happily all over the world in decades of international travel.

EDIT: Note user Dezza's comment below, with which I agree. Here's an Amazon photo of an adapter with a fully-exposed ground pin:

There are more elegant solutions (replace the Apple power cord with a made-for-the-UK cord and plug, replace the charger's "duck head" so the charger itself plugs directly into the UK socket, add additional sockets to the assembly so you can plug in additional US devices) but these are at least a little more complicated, and apt to be more expensive.

First, iPhones sold worldwide are pretty much the same. The different markets get some software differences and some differences regarding wifi or cell standards, but the charging is 100% the same for a given model. This is true for both wired and wireless charging.

iPhones (all of them, from the first iPhone with no number all the way to the last 14 (or was it 15 already? ) use USB charging.

The plug from the iPhone side is not a standard USB, but if the cable is detachable from the charger, the charger side is always a standard USB-A (older ones) or USB-C (newer ones).

In an emergency, any USB charger or a computer USB port that has the corresponding female USB-A or USB-C will do. But it may not be the most efficient solution (the charging may be way slower than expected)

Depending on the iPhone model, one may want to use USB-A 2.4 ampere charger (the older iPhone models) or USB-C with USB-PD charging protocol (iPhone 8 and later).

Of course, one can just get a local iPhone charger for the corresponding iPhone model, but this has little or no value (other than paying premium for the brand).

I strongly advice against using AC plug adapters.

While some of them can work and even save the day, they also have traditionally low build quality, loose electrical contacts that can spark and arc (fire hazard!) and enable plugging things in an electrical grid with the wrong voltage.

Using an AC plug adapter one also generally loses a lot of protections that the local power grid offers (e.g. grounding).

In the strict sense, plug adapters are generally illegal in most electrical codes around the world. For a reason.

Here is what Apple themselves offer for chargers (retrieved today from Apple's UK website via a VPN):

Depending on the age of your cell phone you may or may not have the right Lightning cable (older ones were USB-A, now they are USB-C). So it could cost as much as 38 GBP.

Plug adapters seldom are officially safety approved for the places where they are actually used. Most of them are safe enough provided whatever is plugged in is double insulated. Laptops with a ground pin can often find the ground flapping in the breeze- for example one travel adapter I have sports a plastic UK ground pin and two-pin plug for EU, but happily receives a 3-pin US-style plug.

To be 100% safe I would limit myself to buying the chargers sold in the official Apple store. Failing that, get a known brand name. There are poor quality units about. That said, it's rare (but quite possible) for them to actually destroy a phone. Isolation is also a potential risk- there have been rare cases of fatal shocks delivered through faulty chargers, and from dismantling a few, many play fast and loose with creepage and other isolation requirements. I don't trust any of them, including Apple, with my life (I won't provide them with a conductive path through my heart should they decide to fail). At best the insulation keeping you from dying is a few thin layers of insulation in the transformer- eg. special wire insulation plus some plastic tape).

In general yes, but there are few problems:

iPhone chargers may be expensive (especially if you intend to leave them behind, so the durability is not so important).

Finding a shop may not be simple: depending on countries they may be closed on Sundays or on evening, and electronic shops may have language problems.

And you may get just USB charger which has very little power. Very annoying in some hotels where power is switched off when you leave the room, or with sockets at inconvenient places.

Personally I try to bring one (and also cables). Sometime I forget them, or with travel they break, for this reasons I found the above problems. Note: many hotels and restaurants may borrow you a charger, or let the phone charge when you are there (and fortunately we are no more in the epoch with "who has the charger for "new Nokia", for "Sony Ericson", etc.? Now iPhone lighting and USB are available everywhere.

You have the choice:

• You can use your existing charger with just an adapter. The charger will accept 230V mains power from the UK exactly as it accepts 120V mains power from the US, the adapter is only needed so that you can insert the plug into the socket. You can buy adapters from nearly anywhere.

• You can buy a new adapter, which will have the right plug (the big bulky UK plug).

  • If you want to re-use your existing cable (or maybe a MagSafe charger), make sure the output of the charger is the same (most common chargers have the older USB-A output, some more recent chargers have the newer and smaller USB-C output). Note that if you buy a charger with a cable, it needs to have a Lightning port to connect to your iPhone.

  • While any charger will work, not all chargers are created equal. Some provide very little power, and it will take longer to recharge your phone. Better chargers provide more power, which can make charging quicker if they are compatible with your phone. Chargers with an USB-C output should all be compatible, while for chargers with an USB-A output YMMV.

Since you have an iPhone, the easiest (but not cheapest) way to be sure is to buy the charger from Apple. The current standard charger is the "20W USB-C Power Adapter" (just under £20). It has an USB-C output (so you need your cable to be USB-C to Lightning), and does not come with a cable.

Alternatively, some Apple chargers (and others) have two parts: the charger itself, and the plug. It's then possible to change just the plug (using the brand's World Travel Adapter Kit.

Disclaimer: I don't own an iPhone, I'm basing my answer on my experience with Android phones.

First of all, the iPhones sold in the UK are the same (at least charging-wise) as in the US, only the charger is different (and most probably only the charger plug). So you can buy a charger in the UK and it will work with your iPhone (just make sure that it's indeed lightning).

However, as Giacomo Catenazzi has correctly noted, shopping for a charger may be inconvenient for many reasons, and you may get only a cheap charger that will take a lot of time to charge your iPhone.

I would also add that an iPhone charger (unlike many other things such as a spare TShirt or even a laptop charger) is a thing that you may want to have immediately on arriving to your hotel (think how long your trip will be and how much charge will remain in your iPhone after that time, take into account whether you'll be using your iPhone while on the plane, thus draining the battery). You probably do not want to spend a couple of days with a dead iPhone just because you can not find a charger. (And finding a store with a dead iPhone can also be a challenge!)

Also, you may need your charger during the trip: electric outlets are common in the airports, stations, trains, etc, even some planes may have them, and it is very convenient to have a charger at hand to charge your iPhone while you are waiting for your flight.

Takeaway: buying a charger is possible, but may be very inconvenient.

At the same time, your charger most probably will work in the UK provided you have an adapter. There are two things that are different in the UK as compared to the US: the voltage and the plug type.

As for the plug, you can easily buy an adapter, it does not contain any electronics inside, it simply allows you to connect the charger plug to the outlet. An adapter will be useful to your anyway (are you bringing a laptop with you? maybe other electric equipment such as a camera charger?), so it'll be a good idea to buy a few adapters before you leave the US. They must be very cheap.

The voltage is a different beast, some electric devices can burn when plugged to a higher UK voltage. But almost all modern chargers and other simple consumer equipment can run both on US 120 V as well as the UK 230 V. Your charger most probably has allowed voltage marked on it, you may check it to be sure; my charger reads "Input: AC 100-240V".

Takeaway: your charger should work provided you buy an adapter; look at the marking on your charger to be absolutely sure.

So personally I would not only take a charger (and an adapter or two) with me, but also put it into hand luggage.

All chargers worldwide put out the same power regardless of input. So yes, you can just buy a new charger.

It might even be cheaper than buying an adapter.