How to Dial International Numbers: +, 00, Codes

Every international phone number is built from the same few parts, yet dialing one still trips people up: a call that works from Germany fails from the US, a number copied from a website rings nowhere, a saved contact stops working on holiday. This guide takes an international number apart piece by piece — the + sign, exit codes like 00 and 011, country codes, area codes and the troublesome leading zero — so you can dial any number in the world from any phone, correctly, on the first try.

The anatomy of an international number

Take a Berlin landline written in full international format: +49 30 123456. Reading left to right:

Mobile numbers follow the same pattern, except the middle part identifies a mobile network instead of a city: a German mobile looks like +49 1512 3456789, a Nigerian one like +234 802 123 4567.

The + sign: one prefix that works everywhere

The + is not a real digit you send down the line — it is shorthand for "insert my country's international exit code here". Every mobile phone made in the last two decades understands it: press and hold the 0 key and the + appears. When you dial +291 7 123 456, your phone substitutes the right exit code for whatever country you happen to be standing in.

That is exactly why the international format is the only format worth saving. A contact stored as +44 20 1234 5678 dials correctly from London, Lagos or Los Angeles; the same number stored as 020 1234 5678 only works inside the UK.

Exit codes: 00, 011 and the other ways out

Before the + sign existed, every country defined its own "way out" — the prefix that tells the network the call is leaving the country. They are still there, and you will still meet them on landlines, office phones and older mobiles:

If you only remember one row of that table, make it the last one.

Country codes: 1 to 3 digits, no overlaps

Country codes were handed out by world region, which is why neighbours often share a first digit: 1 covers the United States and Canada, codes starting with 3 and 4 are European — the United Kingdom is +44, Germany +49, Italy +39 — and most of Africa starts with 2: Nigeria is +234, Ethiopia +251, Eritrea +291.

The codes are designed so that no complete code is the start of another — +1 exists, so no other code starts with 1. Your phone therefore always knows where the country code ends and the rest of the number begins, even without the spaces.

Here are ten popular destinations with their codes and a correctly formatted example mobile number — each links to its live per-minute rate:

Every other country's code, current call rate and number format is on our all-destinations page.

The leading zero: drop it — almost always

Here is the mistake behind most failed international calls. Inside many countries, you dial a 0 before the area code: a Londoner dials 020 1234 5678, a Berliner 030 123456. That zero is a domestic trunk prefix — it means "long distance, within this country" — and it must be dropped when you dial from abroad: +44 20 1234 5678, +49 30 123456.

So when a relative reads you a number starting with 0, replace that zero with + and the country code. Dialing +44 020 … gets you a polite error message, not a ringtone.

The famous exception is Italy: the leading zero of an Italian landline is part of the number itself and stays — a Rome landline is +39 06 1234 5678, zero included. Italian mobiles, on the other hand, never had the zero. If in doubt, the number format on each of our country pages shows a correctly formatted example for that country.

Area codes: the address inside the country

For landlines, the digits after the country code pin the call to a city or region: 20 is London, 1 is Paris, 212 is New York, 11 is Addis Ababa, 1 is Lagos. Big cities got short codes back when digits were scarce, so the pattern is a rough map of telephone history — Mexico City is 55, Mumbai is 22.

Two things follow from this. First, an area code is never optional when calling from abroad — there is no "default city". Second, mobile numbers have no geography at all: a UK number starting +44 74… belongs to a person, not a place, and travels with them. Each eFon country page lists the area codes of the major cities, so you can also tell at a glance where an unfamiliar landline number is ringing.

The four classic mistakes

1. Keeping the leading zero — +44 020… instead of +44 20… (unless it's an Italian landline).
2. Dialing the country code twice — a number copied as 0049 30… and then dialed with +49 in front.
3. Saving contacts in local format — works at home, breaks the moment you or the number crosses a border.
4. Assuming 00 works from the USA — it doesn't; North America's exit code is 011. The + avoids the question entirely.

Save it once, dial it forever

The practical takeaway fits in one sentence: store every foreign contact in full international format, starting with +, and you will never think about exit codes or trunk prefixes again.

From there, the cost is the only thing left to fix. In the eFon app you pick the contact from your normal phone book and the app handles every prefix for you — and because the expensive international leg travels over the internet, you pay one clear per-minute rate with no connection fee, up to 90% less than dialing the same number directly on your mobile operator's plan. Only your side needs internet: the other person answers a regular call on their mobile or landline, no app needed. Check the live rate for any destination on its country page — from calls to Eritrea to calls to the United States — dial the number in its proper + format, and the hardest part of an international call becomes deciding what to talk about.