Mauritius Phone Numbers: Format, Area Code & Validation Guide

This guide provides a comprehensive overview of the Mauritius phone numbering system, including formatting, validation, and best practices for developers. It covers key technical details and regulatory considerations to ensure your applications handle Mauritian phone numbers correctly.

Quick Reference

• Country: Mauritius
• Country Code: +230
• International Prefix: 00
• National Prefix: None
• Regulatory Authority: Information and Communication Technologies Authority (ICTA) (https://icta.mu/)
• Emergency Numbers: 999 (Police), 114 (Fire), 115 (Ambulance)

Numbering System Overview

Mauritius adheres to the ITU-T Recommendation E.164 standard, ensuring global compatibility. The system supports mobile number portability (MNP), a crucial factor for developers to consider. Regular compliance checks with ICTA regulations are mandatory.

Key Considerations for Developers:

• E.164 Formatting: Store and process all numbers in international format (+230...).
• Mobile Number Portability: Implement MNP checks to accurately identify carriers.
• ICTA Compliance: Stay updated on current regulations and incorporate necessary changes.
• Comprehensive Validation: Validate both format and number type.

Number Format Specifications

Mauritian phone numbers follow a structured format:

+230 [Number Type Prefix] [Subscriber Number]

The Number Type Prefix indicates whether the number is geographic (landline), mobile, or belongs to a special service category.

Geographic (Landline) Numbers

• Format: +230 2XXX XXXX (8 digits after the country code)
• Validation Regex: /^2\d{7}$/ (after removing the country code)
• Example: +230 2123 4567
• Usage: Fixed-line services throughout Mauritius. Area codes are integrated within the subscriber number.

Mobile Numbers

• Format: +230 5XXX XXXX (8 digits after the country code)
• Validation Regex: /^5\d{7}$/ (after removing the country code)
• Example: +230 5912 3456
• Special Considerations: Mobile number portability is active in Mauritius. You must implement a mechanism to determine the current carrier for a given mobile number.

Special Service Numbers

• Toll-Free:
  • Format: +230 800 XXXX
  • Validation Regex: /^800\d{4}$/ (after removing the country code)
  • Example: +230 800 1234
• Premium Rate:
  • Format: +230 30X XXXX
  • Validation Regex: /^30\d{5}$/ (after removing the country code)
  • Example: +230 305 1234
• Other Special Services: The ICTA may allocate other special service prefixes. Consult the ICTA documentation for the most up-to-date information.

Implementation Best Practices

1. Normalization

Normalize phone numbers to the E.164 format before storage or validation. This ensures consistency and simplifies processing.

function normalizeMauritiusNumber(phoneNumber) {
    // Remove all non-numeric characters
    let normalized = phoneNumber.replace(/\D/g, '');

    // Add the country code if missing
    if (!normalized.startsWith('230')) {
        if (normalized.startsWith('00230')) {
          normalized = normalized.replace('00230', '230');
        } else if (normalized.startsWith('0')) {
          normalized = '230' + normalized.substring(1);
        } else {
          normalized = '230' + normalized;
        }
    }

    // Validate length (including country code)
    if (normalized.length !== 11) {
        throw new Error('Invalid number length');
    }

    return '+' + normalized;
}

2. Validation

Implement robust validation to prevent invalid numbers from entering your system.

function validateMauritiusNumber(phoneNumber) {
    const normalized = normalizeMauritiusNumber(phoneNumber);
    const numberWithoutCountryCode = normalized.slice(4); // Remove +230

    // Check number type and apply appropriate validation
    switch(numberWithoutCountryCode[0]) {
        case '2': return /^2\d{6}$/.test(numberWithoutCountryCode);
        case '5': return /^5\d{6}$/.test(numberWithoutCountryCode);
        case '8': return /^800\d{3}$/.test(numberWithoutCountryCode); // Toll-free
        case '3': return /^30\d{4}$/.test(numberWithoutCountryCode); // Premium Rate
        default: return false;
    }
}

3. Number Portability

Use a reliable MNP database or API to determine the correct carrier for mobile numbers. Do not rely on number prefixes to identify carriers, as this information becomes inaccurate with number portability. Regularly update your MNP data to maintain accuracy. The ICTA provides guidelines and resources for handling number portability.

4. Error Handling

Implement comprehensive error handling to gracefully manage invalid numbers and other potential issues.

function handlePhoneNumberError(number, error) {
    const errorTypes = {
        INVALID_FORMAT: 'Invalid number format',
        UNSUPPORTED_TYPE: 'Unsupported number type',
        PORTING_IN_PROGRESS: 'Number currently being ported',
        DATABASE_ERROR: 'Error accessing portability database'
    };

    console.error(`Phone number error: ${error} for number ${number}`);
    return errorTypes[error] || 'Unknown error occurred';
}

Technical Considerations for Scalability

Database Storage

Store phone numbers in a normalized format (E.164) to facilitate efficient querying and processing. Include fields for number type, carrier (for mobile numbers), and validation status.

CREATE TABLE phone_numbers (
    id SERIAL PRIMARY KEY,
    raw_number VARCHAR(20),  -- Store the original input
    normalized_number VARCHAR(15), -- Store the E.164 formatted number
    number_type VARCHAR(10), -- e.g., 'geographic', 'mobile', 'toll-free'
    carrier VARCHAR(50),     -- For mobile numbers
    last_validated TIMESTAMP
);

Caching

Implement caching for MNP lookups and validation results to improve performance. Set appropriate TTL (Time To Live) values based on the frequency of data changes.

const CACHE_CONFIG = {
    portability: {
        ttl: 3600, // 1 hour
        checkPeriod: 600 // 10 minutes
    },
    validation: {
        ttl: 86400 // 24 hours
    }
};

Regulatory Landscape and Future Changes

The ICTA governs the telecommunications sector in Mauritius. They are responsible for maintaining the numbering plan and ensuring compliance with international standards. Be aware that regulations can change, so it's essential to stay informed about updates from the ICTA. For example, the transition to 8-digit mobile numbers (from the previous 7-digit format) demonstrates the dynamic nature of the numbering system. Always consult the official ICTA documentation for the latest information.

Additional Resources

• ICTA Official Website: https://icta.mu/
• ITU-T E.164 Specification: https://www.itu.int/rec/T-REC-E.164/en