Understanding Phone Numbers in Cambodia

Quick Reference Guide

Country: Cambodia
Country Code: +855
International Prefix: 001, 007, 008, 009, 014-019
National Prefix: 0

Overview of Cambodia's Phone Number System

Cambodia's telephone numbering plan aligns with the ITU-T E.164 standard, ensuring seamless international connectivity. This guide offers a comprehensive overview of Cambodia's numbering plan, detailing formats, dialing procedures, and regulatory insights crucial for telecom professionals, developers, and system administrators.

Detailed Number Formats

General Number Structure

Cambodian phone numbers are organized as follows:

Type	Format	Example
Geographic	`0X XXXX XXXX` or `0XX XXXX XXX`	023 123 4567
Mobile	`0X XXXX XXXX` or `0XX XXXX XXX`	012 345 6789
Toll-Free	`1800 XXXX`	1800 1234
Premium Rate	`1900 XXXX`	1900 5678

Geographic Numbers

Geographic numbers in Cambodia are typically 8 to 9 digits long:

Format: 0[2-4] XXXX XXXX
Example: 023 123 4567

Mobile Numbers

Mobile numbers in Cambodia are usually 8 to 9 digits long:

Format: 0[1-9]X XXXX XXX or 0[1-9]X XXXX XXXX
Example: 012 345 6789

Toll-Free Numbers

Toll-free numbers are 8 digits long and start with 1800:

Format: 1800 XXXX
Example: 1800 1234

Premium Rate Numbers

Premium rate numbers are 8 digits long and start with 1900:

Format: 1900 XXXX
Example: 1900 5678

Validating Phone Numbers with Regular Expressions

Use these regex patterns to validate Cambodian phone numbers:

Geographic Numbers:
```
^0[2-4]\d{7,8}$
```
Mobile Numbers:
```
^0[1-9]\d{7,8}$
```
Toll-Free Numbers:
```
^1800\d{4}$
```
Premium Rate Numbers:
```
^1900\d{4}$
```

Dialing Procedures in Cambodia

Domestic Calls

Landline to Landline: Dial the full number (e.g., 023 123 4567).
Landline to Mobile: Dial the full mobile number (e.g., 012 345 6789).
Mobile to Mobile: Dial the full mobile number (e.g., 012 345 6789).

International Calls

Outgoing: Dial the international access code (e.g., 001), followed by the country code and the subscriber number. Example: 001 1 555 123 4567 for the USA.
Incoming: Dial +855 followed by the local number without the leading 0. Example: +855 23 123 4567.

Number Portability

Currently, Cambodia does not support mobile number portability (MNP), meaning numbers cannot be transferred between different operators.

Major Telecom Operators and Their Number Ranges

Operator	Number Range Prefixes
Cellcard	012, 017, 077, 078
Smart	010, 015, 016, 069
Metfone	097, 088, 031, 081
qb	013, 080
CooTel	038

ITU-T Recommendations

Cambodia complies with the ITU-T E.164 standard, ensuring that phone numbers are globally unique and correctly routed internationally.

Number Allocation and Management

The Ministry of Posts and Telecommunications of Cambodia (MPTC) is responsible for the allocation and management of phone numbers, ensuring compliance with international standards and managing number ranges for telecom operators.

Technical Restrictions and Special Cases

Golden Numbers

"Golden numbers," which are easy to remember, are often reserved or sold at a premium, featuring repeating digits or recognizable patterns.

Number Blocking

Certain numbers may be blocked due to non-payment or misuse, with operators enforcing these restrictions under regulatory guidelines.

Technical Considerations for Developers

When developing applications or systems handling Cambodian phone numbers, consider the following:

Validation: Utilize the provided regex patterns for validation.
Formatting: Store and display numbers in the correct format (0XX XXXX XXX).
Internationalization: Implement logic for both domestic and international dialing formats.
Error Handling: Prepare for issues like number blocking or invalid formats.
Regulatory Compliance: Ensure adherence to MPTC regulations regarding number usage and data privacy.

For the latest telecommunications regulations in Cambodia, visit the official MPTC website.