Area Code 21 – Cork
The phone area code for Cork is 21 (international format +35321). Browse local exchange codes (NXX) and carrier assignments below.
📞 Exchange Codes (NXX) for Area Code 21
Select a central office code to view local carrier data and detailed information
📍 Geographic Location of Cork
Overview of Area Code +353 21
Area code 21 is the geographic National Destination Code (NDC) for the city of Cork and its surrounding county in the Republic of Ireland. Assigned under the national numbering plan administered by ComReg, this code is used for fixed-line (PSTN) and fixed-wireless services. The international dialing format is +353 21 X XXX XXX (where X represents the subscriber number digits). Within Ireland, callers dial 021 X XXX XXX without the leading '+' and country code.
Geographic Coverage and Administrative Jurisdiction
The code covers the entire County Cork, including the city of Cork, which is the second-largest city in Ireland. It serves major towns such as Ballincollig, Carrigaline, Cobh, Midleton, Mallow, Fermoy, and Bantry. The area is part of the South-West region of Ireland and is a major economic hub, home to many multinational corporations, the Port of Cork, and University College Cork.
Dialing Formats and Caller Instructions
For local callers within Ireland, the trunk prefix '0' is used: 021 234 5678. For international callers, the country code +353 is used, and the leading '0' is dropped: +353 21 234 5678. When dialing from a mobile phone in Ireland, it is common to use the international format even for domestic calls, as it is unambiguous and works for all numbers.
There are no overlay codes in the Cork area; the 021 code is the sole geographic code for the region. Subscriber numbers are seven digits long, making the total number length 9 digits when including the NDC (without the leading '0').
Numbering and Regulatory Notes
Since 2007, Ireland implemented a measure allowing subscribers to retain their geographic numbers when moving within the same area code, but number portability also permits moving a geographic number to a VoIP service, which may not be tied to a physical location. However, the 021 code remains primarily associated with fixed-line services in the Cork region.
For businesses, having a Cork number can establish a local presence, and calls to 021 numbers are typically charged at standard national rates when dialed from within Ireland. From abroad, charges depend on the international tariff of the calling country.
When dialing from outside Ireland, always replace the leading '0' with the country code +353. For example, a Cork number 021 555 1234 becomes +353 21 555 1234 internationally.