What is ISD code ?

What is ISD Code? | What is International Calling Code?

ISD code means unique international subscriber dialing (ISD) code of each contry that are prefixed for telephone subscribers in the Internation Tele Communication Union (ITU).

Country calling codes are prefixes and a component of international telephone numbering plan and becomes mandatory when calling from one country/nation to another contry/nation. These are prefixed before the actual telephone number and usually, start with (+) and followed by country code, followed by the respective telephone number.

Your Ultimate Guide to ISD Codes

An ISD code (International Subscriber Dialing) is a prefix number used when making international calls. Each country is assigned a unique ISD code, also known as a country code or IDD code (International Direct Dialing). These codes are essential for connecting with phone numbers worldwide.

How ISD Codes Work

ISD codes function as identifiers for specific countries in the global telephone network. When you dial an international number, the ISD code indicates the country where the call is directed.

To make an international call, you typically follow this format:

  1. + (Plus Sign): Start with a plus sign to signal an international call.
  2. ISD Code: Enter the ISD code of the country you're calling.
  3. Area Code (if applicable): Some countries require an area or city code before the local number.
  4. Local Phone Number: Dial the recipient's phone number.

Example: To call a UK number (ISD code +44) in London (area code 20) with the local number 712345678, you'd dial: +44 20 712345678

Why ISD Codes Matter

  • Global Communication: ISD codes make it possible to reach anyone, anywhere, fostering international connections for business, personal relationships, and emergencies.
  • Standardized Dialing: They provide a unified system, simplifying international calling regardless of your location.
  • Call Routing: ISD codes help telephone networks accurately route calls across borders.

Finding ISD Codes

There are several ways to find ISD codes:

  • Codes.in: Our website offers a comprehensive, searchable directory of ISD codes for every country.
  • Other Online Directories: Numerous websites and apps specialize in listing ISD codes.
  • Phone Books: Many printed phone books include a section on international dialing codes.
  • Your Phone Carrier: Your mobile carrier's website or customer service can provide ISD code information.

Tips for Using ISD Codes

  • Double-Check: Always verify the correct ISD code before making an international call, as errors can be costly.
  • Mobile Phones: Most mobile phones automatically handle the "+" prefix, simplifying international dialing.
  • Carrier Costs: International calls may incur extra charges. Check with your service provider for rates.

Common ISD Codes (Examples)

Country ISD Code
United States +1
Canada +1
United Kingdom +44
Australia +61
India +91
Germany +49
China +86
Japan +81
France +33
Brazil +55


ISD codes, country codes, and IDD codes all refer to the same thing. Some countries may have multiple ISD codes for different regions or carriers. Always be aware of your carrier's international calling rates. Use [Your Website Name] for a quick and easy way to look up ISD codes!