How to Call the US from the UK? Dialing Steps & Tips

The US phone number format for international calls when calling from the UK includes the UK international access code (IAC), the US country code, the area code, and the subscriber number. This combination ensures your call is correctly routed from the UK to the specific region and number within the United States.

1. IAC or Exit Code: When making a call from the UK to the United States, you first need to dial the IAC. In the UK, the IAC is 00. However, if you’re calling from a mobile phone, you can replace “00” with the “+” symbol, which is often more convenient.
2. Country Code: After the exit code, you must include the country code for the United States, which is 1. This number identifies the US in the global telephone network and must be dialed before the area code.

3. Area Code: The area code identifies the specific city or region within the United States. Each area code represents a specific area, city, or part of a state, helping direct your call to the right place.
   
   The table below illustrates some of the popular area codes in the US you may like to reach out to.

   Area Code	City
   212	New York City
   415	San Francisco
   213	Log Angeles
   225	Baton Rouge
   417	Springfield
   424	Los Angeles
   305	Miami

4.  Subscriber Number: This is the individual phone number belonging to a person or business within the area code. Together with the area code, it makes up a standard 10-digit US number.

To call a USA landline number from the UK, dial the UK exit code (00), followed by the US country code (1), the area code, and the subscriber's landline number. Similarly, to call a US mobile number from the UK, dial the UK exit code (00), followed by the US country code (1), the area code, and the subscriber's mobile number.

To call a US landline number from the UK:

• Step 1: Dial the UK international access or exit code
• Step 2: Dial the US country code
• Step 3: Enter the area code
• Step 4: Add the subscriber's landline number

For example, to connect with someone with a USA landline number from England, dial 00 1 212 1234567.

Where,

• 00 - Exit code of the UK
• 1 - US country code
• 212 - Area code of New York
• 1234567 - Recipient’s landline number

To call a US mobile number from the UK:

• Step 1: Add the UK exit code
• Step 2: Dial the US country code
• Step 3: Enter the area code
• Step 4: Dial the subscriber's mobile number

For example, to connect with someone with a USA mobile number from the UK, dial 00 1 212 1234567. Or, using the plus sign: +1 212 1234567.

Where,

• 00 - Exit code of the UK
• 1 - US country code
• 213 - Area code of California
• 1234567 - Recipient’s cell phone number

To call a US toll-free number from the UK:

• Step 1: Dial the exit code of the UK
• Step 2: Dial the US country code
• Step 3: Enter the toll-free prefix
• Step 4: Dial the toll-free number

For example, to connect with someone with a US toll-free number, dial 00 1 880 1234567 or +1 880 1234567.

Where,

• + - International dialing prefix (When calling from a cell phone)
• 1 - US country code
• 880 - Toll-free prefix
• 1234567 - Recipient’s toll-free number

However, it’s important to note that most US toll-free numbers cannot be reached directly from outside the country. Even if the call connects, the number will not be toll-free, and you’ll likely be charged international calling rates.

The best time to call the USA from the UK is between 2:00 PM and 12:00 AM (UK time). This time window overlaps with the standard US business hours (9:00 AM to 5:00 PM) across most American time zones.

The United Kingdom operates on Greenwich Mean Time (GMT) or British Summer Time (BST, GMT+1), depending on the season. The United States, on the other hand, spans six major time zones, from the Eastern Time Zone (ET) to the Hawaii-Aleutian Time Zone (HST). This means there can be a time gap of 5 to 10 hours between the UK and different parts of the US.

To help you plan your calls, here's a table of the best calling windows (UK time) that correspond to 9 AM – 5 PM in each US time zone:

On average, calling the United States from the United Kingdom costs between $2 and $5 per minute, depending on your phone provider, the number type (landline or mobile), and the specific plan you have. Traditional network carriers usually charge higher international calling rates, making long conversations quite expensive.

Below are some of the calling rates charged by major UK mobile providers for calls to the United States:

Some cost-effective options to call the US from the UK are virtual numbers, messaging apps, or international calling cards. They offer lower per-minute rates, reliable connections, and help reduce the high costs of international communication.

A virtual number is a phone number that works over the internet instead of traditional phone lines, allowing you to make and receive calls at a much lower cost. With a virtual number provider like Calilio, you can obtain a local US number even while you’re in the UK, so you can reach people in the US as if it were a domestic call.

Apps that use your internet connection (Wi-Fi or mobile data), such as WhatsApp, Viber, Telegram, or FaceTime (for iOS), let you make voice/video calls to the US at little to no extra cost. If both parties have the app, calls are often free.

Calling card services allow you to prepay for international calling minutes, which you can then use to make calls to US numbers at lower rates than standard phone plans. However, it’s important to note that rates and call quality can differ between providers, and some cards may include hidden charges or connection fees.

Making a call from the UK to the US doesn’t have to be complicated. Once you understand the correct dialing format, you can connect quickly and confidently. But to make your conversations smooth and cost-effective, it’s equally important to consider time zone differences and calling costs.

While traditional phone carriers often charge high international rates, there are smarter, more affordable alternatives. Using virtual numbers, messaging apps, or international calling cards can help you stay connected without overspending.