To call London from a US cell phone, dial +44 20 followed by the local London number. The plus sign (+) automatically replaces the US exit code (011), so you can simply hold the + key on your phone’s keypad instead of dialing 011.
How to call London from a US cell phone in 3 easy steps
- Open your phone’s dialer and press and hold the “0” or “+” key until a plus sign (+) appears.
- Dial the UK country code: 44.
- Dial London’s area code (20) and then the local 8-digit London number. Do not include the leading “0” that is used when dialing within the UK.
For example, if the local London number is 020 7123 4567, you would dial +44 20 7123 4567. The plus sign works on any US cell phone and is the simplest way to handle international calling codes and dialing.
Understanding London phone numbers and UK country codes
The UK country code is +44. London’s area code is 20, which covers most of the city including Central London, Inner London, and many outer boroughs. When you call a UK number from a US cell phone, you must drop the leading “0” from the area code. This format applies whether you are dialing a landline or a mobile number in London.
Cheapest ways to call London: carrier plans vs. VoIP
Major US carriers like Verizon, AT&T, and T-Mobile offer international calling plans or add-ons that provide discounted or unlimited calls to the UK. These plans typically require a monthly subscription or a daily pass. Some international calling plans include text messaging and data usage features beyond just voice calls. For example, you can check international calling rates via T-Mobile to see if their add-on covers London at a flat rate. Alternatively, Voice over Internet Protocol (VoIP) services can be significantly cheaper. Google Fi plans offer international calling to the UK, with some plans including it at no additional cost or at affordable per-minute rates. Note that Skype for consumer international calling was shut down in May 2025 and replaced by Microsoft Teams; its previous pay-as-you-go rates are no longer applicable. International calling cards require dialing an access number, entering a PIN, then dialing the London number. You need sufficient calling credit on your US cell phone before making international calls. VoIP providers should have servers in London to ensure optimal call quality. Compare your carrier’s international add-on with a VoIP service to find the lowest cost for your calling volume.
Using Wi-Fi calling to phone London
Wi-Fi calling can be used to make international calls from a US cell phone. If you have a stable Wi-Fi connection, enable Wi-Fi calling in your phone’s settings. When using Wi-Fi calling while abroad, calls to US numbers are typically not billed, but calls to international numbers (including London) may still incur charges based on your international calling plan. So even though you are connected to Wi-Fi, the call to a London number will be charged according to your carrier’s international rates or add-on plan. This feature is most useful when your cellular signal is weak, but it does not automatically make the call free.
Frequently Asked Questions
Will I be charged extra for calling London from my US cell phone?
Yes, standard domestic plans do not include international calls. You will be billed at your carrier’s per-minute rate unless you have an international calling add-on or plan. Check with Verizon, AT&T, or T-Mobile for their specific UK rates before dialing.
Can I text a London number from my US cell phone?
Texting a UK mobile number from the US works the same way as calling: use +44 followed by the mobile number without its leading “0”. Standard SMS rates for international texting apply unless your plan includes international messaging.
What if my US cell phone shows “invalid number” when I dial London?
This usually means you omitted the plus sign or the country code, or you included the leading “0” from the UK number. Make sure you dial exactly +44 20 followed by the 8-digit local number, with no spaces or extra digits.
Is there a cheaper alternative to using my cell phone to call London?
Yes. VoIP apps like Microsoft Teams or Google Fi can offer lower rates. You can also use a prepaid international calling card, which you dial from your cell phone and then enter a PIN before the London number. Compare per-minute costs before choosing.
