Ascension Island Phone Numbers: Format, Area Code & Validation Guide

Introduction

Ascension Island phone numbers use the +247 country code with 4-digit mobile and 5-digit landline formats. The +247 calling code is essential for international dialing to this British Overseas Territory. This guide equips developers and system administrators with practical knowledge for validating, storing, and implementing Ascension Island telecommunications integration.

What you'll learn:

• +247 country code formats and validation patterns
• Regulatory framework and E.164 compliance requirements
• Implementation with JavaScript regex and SQL examples
• Database schema design and storage best practices

Use this guide when developing applications that validate international phone numbers, configuring business communication systems, or integrating Ascension Island contacts into your CRM.

Historical and Regulatory Context

Ascension Island's telecommunications evolved from the first telegraph cable station established in 1898. Today, Sure South Atlantic Ltd operates the modern infrastructure, providing fixed line, mobile roaming, broadband, and data centre services.

Current Operator: Sure South Atlantic Ltd (acquired by Beyon, formerly Batelco Group, in April 2013; managed as part of Beyon since January 2017). Customer Care operates Monday–Friday 9:00–12:00 and 13:00–15:00 (closed weekends).

Regulatory Status: Sure South Atlantic holds an exclusive telecommunications license from the St Helena Government, expiring July 1, 2025. New telecoms legislation and licensing terms are under development by the Ascension Island Government to ensure service continuity beyond this date.

Key Infrastructure Details:

• Satellite-only connectivity via Intelsat AgileCore UX service (February 2025 expanded agreement) – no submarine cables as of 2025
• All international traffic routes through satellite, resulting in higher latency and capacity constraints compared to cable-connected territories
• GSM cellular network deployed in 2012, covering Georgetown, Wideawake Airfield, Travellers Hill, and Two Boats Village
• 2G and 4G services (LTE band 3, 1800 MHz) launched in 2016, using equipment from Star Solutions International Inc.
• Numbering plan reformed on 1 June 2015: geographic numbers expanded from 4 to 5 digits and prefixed with "6"

Ascension Island's telecommunications operate under dual regulatory oversight. Sure South Atlantic Ltd manages local licensing and number range allocation. Internationally, compliance with ITU-T E.164 (11/2010) ensures global interoperability. Learn more about international E.164 phone number format standards.

Ascension Island Phone Number Formats (+247)

Ascension Island uses a straightforward numbering structure that reflects the island's small population:

• Country Code (Calling Code): +247 (assigned by ITU-T)
• National Significant Number (NSN): 4 to 5 digits

Mobile vs Landline Number Formats

Geographic Numbers (Landlines)

Landline numbers follow this format:

Format: 6[2-47]XXX
Examples: +2476223 (US Base)
          +2476312 (Travellers Hill & Airhead)
          +2476441 (Two Boats)
          +2476678 (Georgetown)

Geographic Allocations:

• 62XXX: US Base
• 63XXX: Travellers Hill & Airhead
• 64XXX: Two Boats
• 66XXX–67XXX: Georgetown

The first digit "6" distinguishes landlines, while the second digit identifies the specific area.

Historical Note: Before 1 June 2015, geographic numbers used a 4-digit format. Legacy systems may still contain old 4-digit landline numbers. When migrating data, validate against both old and new formats.

Mobile Numbers

Mobile numbers use a concise, easily identifiable format:

Format: 4XXX
Examples: +2474941 (Personal mobile)
          +2474242 (Business mobile)

The leading "4" marks these as mobile numbers, simplifying identification in your applications.

Non-Geographic Numbers

Non-geographic numbers serve specialized services not tied to physical locations:

Format: 50XXX–59XXX and 8XXXX–9XXXX
Examples: +24750123 (Special service)
          +24780001 (Premium service)

Allocations:

• 50XXX–59XXX: 5-digit non-geographic services
• 8XXXX–9XXXX: 6-digit non-geographic services

These ranges typically include premium rate services, special access numbers, and administrative functions. Validate these separately if your application handles billing or service-type routing.

Number Format Best Practices

Follow these practices when working with Ascension Island phone numbers:

• E.164 Format: Store phone numbers in international E.164 format (+247XXXX) per ITU-T E.164 (11/2010). Read our complete guide to implementing E.164 phone number standards.
• Input Validation: Implement validation on both client and server sides. Handle edge cases and international format variations.
• Data Type: Use VARCHAR(15) in your database schema to accommodate the full E.164 format. Add a separate field for the national number for easier querying.

How to Call Ascension Island: International Dialing Guide

Local Calls Within Ascension Island

Dial the 4 or 5-digit number directly.

Example: To call 6223, dial 6223.

International Calls to Ascension Island

From Ascension Island (outgoing): Dial 00 + Country Code + Number

To Ascension Island (incoming): Dial +247 + Local Number

Dialing Ascension Island from Different Countries

For mobile devices, you can use the + symbol instead of the exit code: +247-[number]

How to Validate Ascension Island Phone Numbers: Developer Implementation

JavaScript Regex Validation for +247 Numbers

Validate Ascension Island phone numbers using these regular expressions:

// Validation regex for all Ascension Island numbers in E.164 format
const ascensionNumberRegex = /^\+247(?:4\d{3}|6[2-47]\d{3})$/;

// Separate validators for mobile and landline
const ascensionMobileRegex = /^\+2474\d{3}$/;
const ascensionLandlineRegex = /^\+2476[2-47]\d{3}$/;

// Comprehensive validator including non-geographic numbers
const ascensionAllNumbersRegex = /^\+247(?:4\d{3}|6[2-47]\d{3}|5[0-9]\d{3}|[89]\d{4})$/;
const ascensionNonGeographicRegex = /^\+247(?:5[0-9]\d{3}|[89]\d{4})$/;

// Validation function
function validateAscensionNumber(phoneNumber) {
    return ascensionNumberRegex.test(phoneNumber);
}

function validateAllAscensionNumbers(phoneNumber) {
    return ascensionAllNumbersRegex.test(phoneNumber);
}

function getNumberType(phoneNumber) {
    if (ascensionMobileRegex.test(phoneNumber)) return 'mobile';
    if (ascensionLandlineRegex.test(phoneNumber)) return 'landline';
    if (ascensionNonGeographicRegex.test(phoneNumber)) return 'non-geographic';
    return 'invalid';
}

// Test cases
console.log(validateAscensionNumber('+2474123')); // true – Valid mobile
console.log(validateAscensionNumber('+2476234')); // true – Valid landline
console.log(validateAscensionNumber('+2476834')); // false – Invalid (8 not in [2-47])
console.log(validateAllAscensionNumbers('+24750123')); // true – Valid non-geographic (5-digit)
console.log(validateAllAscensionNumbers('+24780001')); // true – Valid non-geographic (6-digit)
console.log(validateAllAscensionNumbers('+24790000')); // true – Valid non-geographic (6-digit)
console.log(validateAscensionNumber('+14155552671')); // false – Invalid country code
console.log(validateAscensionNumber('4123')); // false – Missing country code
console.log(getNumberType('+2474123')); // 'mobile'
console.log(getNumberType('+2476223')); // 'landline'
console.log(getNumberType('+24750123')); // 'non-geographic'
console.log(getNumberType('+24780001')); // 'non-geographic'

This regex checks for the correct country code (+247) followed by either a valid mobile (4XXX) or landline (6[2-47]XXX) format. For advanced validation techniques, see our comprehensive E.164 phone number validation guide.

Edge Cases to Handle:

• Legacy 4-digit landlines: Pre-2015 numbers may lack the "6" prefix. Consider accepting both formats during migration periods.
• Mixed NSN lengths: Ascension Island uses 4-digit (mobile) and 5-digit (landline) formats. Ensure your validation handles both lengths rather than assuming a fixed NSN length.
• Non-geographic numbers: If your application handles premium services or special access numbers, validate 5-digit (50XXX–59XXX) and 6-digit (8XXXX–9XXXX) non-geographic formats separately. These may require different billing or routing logic.

SQL Database Schema for Storing Ascension Island Phone Numbers

Incorporate Ascension Island phone numbers into your database:

CREATE TABLE phone_numbers (
    id SERIAL PRIMARY KEY,
    country_code VARCHAR(4) NOT NULL DEFAULT '+247',
    national_number VARCHAR(6) NOT NULL,
    number_type ENUM('landline', 'mobile', 'non-geographic') NOT NULL,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    CONSTRAINT valid_mobile CHECK (
        (number_type = 'mobile' AND national_number ~ '^4\d{3}$')
    ),
    CONSTRAINT valid_landline CHECK (
        (number_type = 'landline' AND national_number ~ '^6[2-47]\d{3}$')
    ),
    CONSTRAINT valid_non_geographic CHECK (
        (number_type = 'non-geographic' AND national_number ~ '^(5[0-9]\d{3}|[89]\d{4})$')
    )
);

-- Index for faster lookups
CREATE INDEX idx_phone_numbers_national ON phone_numbers(national_number);

This schema uses separate CHECK constraints for each number type to enforce valid formats. Note that national_number is now VARCHAR(6) to accommodate 6-digit non-geographic numbers. Adapt this schema to your specific needs.

Common Implementation Challenges and Solutions

Address these challenges when working with Ascension Island phone numbers:

• International Formatting Variations: Users input numbers in various formats. Always convert input to E.164 format before storage or processing.
• Mixed Number Lengths: Unlike countries with uniform NSN lengths, Ascension Island uses 4-digit mobile and 5-digit landline formats. Handle both lengths in your validation logic.
• Legacy System Integration: Older systems may expect longer phone numbers or fixed-width fields. Implement padding or transformations for compatibility.
• Legacy 4-digit Landlines: Pre-2015 landline numbers used 4 digits without the "6" prefix. During data migration, validate against both formats and document which format your system expects.
• SMS Gateway Requirements: Different SMS gateways have specific formatting requirements. Consult your gateway's documentation and test with both mobile formats.

Frequently Asked Questions (FAQ)

What is the country code for Ascension Island?

The country code for Ascension Island is +247, assigned by ITU-T. When dialing from abroad, use +247 followed by the local number (4–5 digits).

How do I validate an Ascension Island phone number?

Ascension Island phone numbers follow these patterns:

• Mobile: +2474XXX (4 digits starting with 4)
• Landline: +2476[2-47]XXX (5 digits starting with 6)

Use the regex pattern /^\+247(?:4\d{3}|6[2-47]\d{3})$/ to validate numbers in E.164 format.

Are Ascension Island phone numbers 4 or 5 digits long?

Both. Mobile numbers use 4 digits (format: 4XXX), while landline numbers use 5 digits (format: 6[2-47]XXX). This changed on 1 June 2015 when landlines expanded from 4 to 5 digits and were prefixed with "6".

Who is the telecommunications provider on Ascension Island?

Sure South Atlantic Ltd, owned by Beyon (formerly Batelco Group) since April 2013, is the sole telecommunications operator. They provide fixed line, mobile roaming, broadband, and data centre services. Customer Care operates Monday–Friday 9:00–12:00 and 13:00–15:00.

How do I call Ascension Island from the United States or UK?

From the US: Dial 011-247-[local number] (011 is the US international exit code)

From the UK: Dial 00-247-[local number] (00 is the UK international exit code)

Example: To call landline 6223, dial 011-247-6223 (US) or 00-247-6223 (UK).

Can I send SMS messages to Ascension Island mobile numbers?

Yes, send SMS to Ascension Island mobile numbers (+2474XXX). The island relies on satellite connectivity with 2G/4G services launched in 2016. Check with your SMS gateway provider for specific formatting requirements and delivery capabilities.

Satellite Connectivity Limitations:

• Higher latency compared to cable-connected territories (all traffic routes via satellite)
• Limited bandwidth capacity may affect message delivery times during peak usage
• Expensive data costs – the largest data package (250 MB) costs 20 SHP (~$25 USD) as of 2025

Test SMS delivery in your application and implement appropriate timeout values to account for satellite latency.

What database format should I use to store Ascension Island phone numbers?

Store numbers in E.164 format (+247XXXX) using VARCHAR(15) to accommodate international standards. Separate the country code and national number into different fields for easier querying and validation per ITU-T E.164 (11/2010) specifications.

What is the area code for Ascension Island?

Ascension Island doesn't use traditional area codes. Instead, the +247 country code covers the entire island. Landline numbers begin with "6" followed by geographic identifiers (62 for US Base, 63 for Travellers Hill, 64 for Two Boats, 66-67 for Georgetown).

Conclusion

You now have comprehensive knowledge of Ascension Island's phone number system, including regulatory context, number formats, dialing procedures, and implementation guidance.

Next steps:

• Implement the validation regex patterns in your application
• Set up your database schema using the provided SQL example
• Test with both 4-digit mobile and 5-digit landline formats
• Handle international formatting variations in user input

Resources for current information:

• Ascension Island Government website
• Sure South Atlantic Ltd Customer Care: Monday–Friday 9:00–12:00, 13:00–15:00
• ITU-T E.164 (11/2010) for international numbering standards

Related guides:

• Saint Helena Phone Numbers (SH) – Sister territory with shared country code history
• E.164 Phone Number Format – International phone number standard specification
• Phone Number Validation Best Practices – Cross-country validation strategies

Ready to implement? Start by testing the JavaScript validation regex with your existing phone number inputs, then migrate to the recommended database schema for long-term maintainability and E.164 compliance.