How to Call the United States from Ireland?

Before calling the US from Ireland, you must know about international dialing codes like exit, country, and area codes, along with calling costs and time differences.

International calls follow a structured format that must be dialed correctly for the call to connect. When calling the United States from Ireland, each part of the number serves a specific purpose.

1. Irish Exit Code (00)

The exit code allows your call to leave Ireland’s telephone network. When dialing internationally from Ireland, this code is 00 and must be entered first. In the case of modern devices like smartphones, you can replace the exit code with “+”. So, the call will not be routed outside the country until and unless you dial the exit code or “+”.

2. US Country Code (1)

After the exit code, you must dial the United States country code, which is 1. This identifies the destination country and ensures your call is routed to the US phone network.

3. US Area Codes

The United States uses three-digit area codes to designate specific regions and cities. Every US phone number includes an area code, whether it is a landline or mobile number. Entering the correct area code is essential for the call to reach the intended recipient.

Unlike Ireland and the UK, the United States does not use a leading "0" as a trunk code for local or international calls. So, adding a "0" before a US area code will cause the call to fail.

The area codes of some popular area codes of the United States are:

Calling the United States from Ireland costs around €0.30 ($ 0.36) to over €1.50 ($ 1.78) per minute, which is typically more expensive than making domestic calls. However, the rates can change depending on the type of service you use, like calling cards, VoIP or internet-based calling. Without the right plan or calling method, international charges can add up quickly.

Although the best time to call the US is office hours (9 AM to 5 PM), the United States spans multiple time zones. This means the local time of the recipient may differ significantly from that of Ireland. Depending on their location, the time difference can be several hours. So, taking this into account is especially important for business or time-sensitive calls to avoid contacting someone outside of reasonable hours.

To call the US from the Republic of Ireland, you need to enter the exit code of Ireland, the country code of America, and the area code of the American city, followed by the local phone number. Here are the detailed steps:

1. Dial the Irish Exit Code: Begin by dialing 00, the international exit code for Ireland or simply press “+”. This signals that you are placing a call outside of Ireland.
2. Enter the US Country Code: After the exit code, dial 1, which is the country code for the United States.
3. Dial the US Area Code: Enter the three-digit area code associated with the city or region you are calling.
4. Dial the Local Phone Number: Finally, dial the remaining seven digits of the local US phone number.

If you are calling a New York number with the area code 212 and the local number 555-1234, you would dial:

00 1 212 555 1234 or +1 212 555 1234

Where,

• 00 or “+” - Exit code of Ireland
• 1 - Country code of the United States
• 212 - Area code of New York
• 555 1234 - Local number

The most reliable ways to call the US from Ireland are carrier calling, using calling cards, VoIP services, and Wi-Fi calling apps.

Using your regular mobile or landline provider is the simplest way to call the US, but it is the most expensive method of calling when compared to other methods. Without a dedicated international plan, Irish providers such as Vodafone, Eir, and Three typically charge €0.30 ($0.36) to over €1.50 ($1.78) per minute.

Some providers offer international add-ons costing around €5 ($5.94) to €10 ($11.89) per month, which lowers per-minute rates. However, any calls outside the included allowance can still be costly, so this option works best for short or urgent calls when you don’t have access to a reliable internet connection.

Calling cards are a good middle ground if you want to keep costs low without committing to a monthly plan. These services usually offer rates of €0.01 ($0.012) to €0.03 ($0.036) per minute for calls to US landlines and mobiles.

Unlike traditional physical calling cards, digital options work through apps or local access numbers and generally provide much better call quality, often with no hidden connection fees. They’re a practical choice for regular callers who want predictable costs and solid reliability.

If you call the US frequently, subscribing to a VoIP service like Calilio can be one of the most cost-effective options. Monthly plans typically range from €7 ($8.32) to €15 ($17.83) and often include unlimited or heavily discounted calls to US numbers.

These services are especially popular with business users, as they usually offer additional features such as voicemail, call forwarding, and the ability to make calls from multiple devices. As long as your internet connection is stable, call quality is generally excellent.

For personal calls, internet-based calling apps like WhatsApp, Messenger, and Viber are often the easiest and cheapest solution. This is because the calls are totally free if you and the recipient are on the same app with a stable internet connection.

That said, call quality depends entirely on your internet connection. If your Wi-Fi or mobile data is unstable, you may experience delays or dropped calls, making this option better suited to casual catch-ups rather than important or time-sensitive conversations.

When calling a US-based phone number from Ireland, the most appropriate time is during standard US business hours, typically 9 AM to 5 PM. Due to the difference in time zones, this generally corresponds from 2 PM to late evening in Ireland, depending on the specific US region.

The table below shows the best times to call from Ireland based on a 9 AM–5 PM workday across different US time zones.

Note: Ireland and the United States switch to and from daylight saving time on different dates. During these transition periods, the time difference may temporarily change by one hour. So, always confirm the local time before scheduling important calls.

Calling the United States from Ireland is straightforward once you understand the correct dialing format, available calling options, and time zone differences. By using the Irish exit code, the US country code, and the correct area code, and avoiding common mistakes such as adding a trunk prefix, you can ensure your call connects without issue.

When it comes to cost and reliability, VoIP services are generally the most effective option for calling the US from Ireland. Reliable providers such as Calilio make it easy to place international calls with lower pricing, clear audio, and flexible calling plans.