Area Code 27 – St. Helena

Geographic Overview and Numbering Context

The +290 27 prefix is a geographic National Destination Code (NDC) assigned to the island of St. Helena, part of the British Overseas Territory of Saint Helena, Ascension, and Tristan da Cunha. This code specifically serves the main island of St. Helena, which is located in the South Atlantic Ocean. The territory's numbering plan is managed under the ITU-T E.164 framework, with the country calling code +290 allocated exclusively to St. Helena and Ascension Island. Unlike larger jurisdictions, St. Helena does not use separate area codes for different towns; instead, the NDC '27' is used for the entire island, covering all fixed-line services within its administrative boundaries.

Dialing Formats and Call Routing

For international callers, the complete number format is +290 27XX XXXX, where '27' is the NDC and the following six digits represent the subscriber number. When dialing from within St. Helena, callers must use the full national number, typically omitting the international access code but retaining the NDC. For example, a local call to a number would be dialed as 27XX XXXX. It is important to note that St. Helena does not have a trunk prefix like '0' used in many countries; therefore, the NDC is always dialed as part of the local number. Calls from mobile networks or VoIP services require the international format +290 27XX XXXX to ensure proper routing through the PSTN.

Service Characteristics and Usage

The '27' prefix is designated for geographic fixed-line services, primarily used by residential and business customers on the island. The numbering capacity is limited due to the small population, and numbers are allocated by the local telecommunications regulator, the St. Helena Government, in coordination with the sole licensed operator, Sure South Atlantic. As of recent years, St. Helena has seen an expansion of broadband and mobile services, but the fixed-line network remains an essential component for government offices, commercial entities, and households. There are no overlay codes or alternative NDCs for St. Helena; the '27' code is exclusive and non-portable across different geographic regions, though number portability within the same operator is possible under specific conditions.

Practical Guidance for Callers

When placing a call to a St. Helena number, international callers should first dial their country's international access code (e.g., 011 from the US, 00 from most European countries), followed by 290, then the NDC and subscriber number. For example, to call a fixed line in Jamestown, the capital, one would dial +290 27XX XXXX. It is advisable to confirm the exact number of digits, as the subscriber number length may vary. Callers should also be aware that St. Helena is in the GMT time zone (UTC+0) and does not observe daylight saving time, which may affect business hours for international communication.