It's easy to keep in touch with people in different countries in this modern age of digital communication. Although many people communicate through social media or internet-enabled calls, a simple phone call is still a popular way to contact others.

You may be trying to phone home when you're on holiday or are trying to reach out to friends and family who are based in the UK whilst you live overseas. It can almost feel like someone is in the same room as you, even if you are separated by thousands of miles.

You may think you know the number you need to dial, but some factors may change the digits. This includes the individual area codes that each country has and whether you make the call from a landline or a mobile phone.

In this guide, we'll look at how UK landline phone numbers can change, depending on where you are calling from in the world and which country you are reaching out to.

To call a UK landline number from another country, you must first dial the international access code from your country. This is usually 00 or 011.

Every country has a country code, which you must dial in addition to the phone number if you call from another country. The UK's code is 44, which you should add after the international access code. After this, you need to dial the UK phone number without the first 0.

For example, you may be trying to contact a London landline with the number 020 7234 3456. The following is a breakdown of what you would need to dial depending on where you were located:

  • Calling from another landline in London: 7234 3456 (as you were within the same area code)
  • Calling from another landline in the UK from somewhere other than London: 020 7234 3456
  • Calling from a mobile anywhere in the UK: 020 7234 3456
  • Calling from a landline from most countries abroad: 00 44 20 7234 3456
  • Calling from a mobile abroad: +44 20 7234 3456

Don't include the leading zero trunk code when writing a UK landline number for someone to call from abroad. This is because the trunk prefix can vary in different countries (although it is zero in most countries). For example, countries participating in the North American Numbering Plan use one as their trunk prefix. This includes places such as the United States, Canada and the Bahamas.

Mobile phone numbers begin with 07 and are 11 digits long. You have to dial the full number if you call from a landline or mobile phone in the UK. However, if you are making an international call to a UK mobile phone, there are a few additional digits to dial.

When calling a UK mobile phone from abroad, you must dial the international code for the country you are phoning from (usually 00 or 011). This is followed by the UK's country code +44. You can then dial the UK mobile number, without the first zero.

For example, if you were phoning the UK mobile number 0712 453 7865, you would dial the following:

  • Calling from overseas landline (most countries): 00 44 712 453 7865
  • Calling from overseas landline (US/Canada): 011 44 712 453 7865
  • Calling from overseas mobile phone: +44 712 453 7865

The amount that you have to pay to call a UK phone number will vary from provider to provider. You may think that it is cheaper to call from a landline, but a call from a mobile phone may be cheaper when using certain phone providers.

As a starting point, the cost to call a mobile phone from a landline (both within the UK) can cost anywhere between 3p to 65p per minute. This is also the range for calling a landline from another landline in the UK. The difference in price is similar to the varying cost of calling a UK number whilst overseas.

Some providers charge the recipient of the call in addition to the person calling. Your call may be rejected if the other person is unwilling to pay the charge and answer the call.

If you need to make regular calls to the UK, one of the most cost-effective ways is to use a VoIP-based phone service. As VoIP calls use a pre-existing internet connection, you won't have to pay as expensive fees per phone call as you would via a landline or mobile phone.

You can make phone calls through a VoIP system as long as you have an internet connection. An internet phone provider enables the same flexibility as a mobile phone because you can make calls wherever you go when you have a connection to Wi-Fi or mobile data.

Zero is the trunk code in the UK and is added to the front of the other digits if you call a UK telephone number from within the country. 00 needs to be added as the exit code if you are phoning from within the UK to make an international call.

You need to add 05 if you call a corporate or VoIP number. 07 is added to the front of mobile phone numbers in the UK, whilst 09 is given to premium rate calls.

Below is a sample of some of the commonly dialled area codes in the UK, but click on the highlighted text to see a full list of UK area codes.

Area CodeLocation

These digits should be added after the exit code of the country that you are calling from and the UK's country code (+44).

Instead of dialling an area code when calling a mobile, you should add the number seven instead, as this is the UK's mobile phone code.

Why did my call to the UK fail?

There are various reasons that your attempt to call a UK landline didn't work. For example, some phone plans in the UK charge the caller and recipient of calls so the person you are trying to contact may have declined your call.
Other reasons that you may be having trouble may be because of the following issues:
The international dialling prefix you have used for your location is incorrect
You haven't omitted the trunk code (the first zero in local numbers)
The recipient of the call has a phone plan that doesn't accept international calls
If you are still experiencing problems and can't make the call, there are alternative options to try. You may be able to make an internet-enabled call through apps like WhatsApp, Skype or Zoom. Many apps also allow video calling, meaning the call will be visual too.
To use internet-enabled calls, you and the person you call must have access to Wi-Fi or mobile data. You might find that the signal is glitchy or the call ends if there isn't a good enough connection.

What is a roaming charge?

A roaming charge is an additional cost that you must pay on top of your standard phone minutes, SMS and data allowance when you use your mobile phone abroad. For example, you will likely have to pay more to call a UK number from outside of the United Kingdom than you would when calling from within the UK.
The roaming charge that you have to pay will depend on your phone plan provider. Data has the most expensive roaming charge, although you will also have to pay extra per minute on a phone call or per text.
You might be able to purchase a bundle that allows you to make a certain amount of calls or texts from outside the UK without paying additional fees. However, once you reach this limit, you will have to start paying per call or text.
It's recommended to contact your phone provider or compare deals online before travelling abroad so that you don't face large charges. Alternatively, you could message and make calls through apps that use an internet connection.

You need to add or omit different area codes and digits when calling a UK landline from abroad. UK telephone numbers begin with +44 for mobiles and 00 for landlines. The trunk prefix may vary for some countries, such as the United States and Canada. Instead of 00, you would need to add 011.

You will need to dial the area code if you are calling a landline, which will usually vary from city to city. Your call won't go through if you omit the area code at the beginning of the phone number when calling from abroad. However, you don't have to use the area code if you are in the UK and calling from within the same city.

The cost to call a landline number in the UK will vary depending on your mobile phone provider. Most companies offer different bundles, which give you a set number of calls, texts and data to use before you have to start paying. It's also a good idea to find out whether you are the only one who will get charged for calling or whether the recipient of the call could also get charged too.