Comprehensive Guide to Phone Numbers in Croatia

Quick Reference

• Country: Croatia
• Country Code: +385
• International Prefix: 00
• National Prefix: 0
• Regulatory Authority: Croatian Regulatory Authority for Network Industries (HAKOM)

Overview of Croatia's Phone Number System

This guide provides a detailed exploration of Croatia's telephone numbering plan, including number formats, dialing procedures, and regulatory aspects. It is designed for telecom professionals, developers, and system administrators who require precise information on the structure and management of phone numbers in Croatia.

Number Formats in Croatia

General Structure

Croatian phone numbers adhere to ITU-T Recommendations E.123 and E.164, consisting of:

• Country Code: +385
• Area Code: 1-9 (varies by region)
• Local Subscriber Number: Length varies by service type (landline, mobile, etc.)

Detailed Number Format Breakdown

Type	Format	Example	Description
Geographic	0X XXX XXXX	01 234 5678	Landline numbers, area code 01 for Zagreb.
Mobile	09X XXX XXX	091 234 5678	Mobile numbers, 09X varies by operator.
Toll-Free	0800 XXX XXX	0800 123 456	Toll-free services for customer support.
Premium	060X XXX XXX	0601 234 567	Premium rate services for entertainment or information.
Emergency	XXX	112	Short codes for emergency services.

Regular Expressions for Number Validation

• Geographic Numbers:
  ^0[1-9]\d{7}$
  

• Mobile Numbers:
  ^09[1-9]\d{6}$
  

• Toll-Free Numbers:
  ^0800\d{6}$
  

• Premium Rate Numbers:
  ^060[1-9]\d{6}$
  

• Emergency Numbers:
  ^112$
  

Dialing Procedures in Croatia

Domestic Calls

• Landline to Landline: Dial the area code followed by the subscriber number, e.g., 01 XXX XXXX for Zagreb.
• Landline to Mobile: Dial the mobile prefix (e.g., 091) followed by the subscriber number.
• Mobile to Mobile: Directly dial the mobile prefix followed by the subscriber number.

International Calls

• Outgoing: Dial 00, then the country code, area code, and local number. Example: 00 44 20 1234 5678 for London, UK.
• Incoming: Callers from abroad should dial +385, followed by the area code (without 0) and the local number, e.g., +385 1 234 5678 for Zagreb.

Number Portability

Croatia supports number portability for both mobile and fixed-line numbers, allowing subscribers to retain their numbers when switching operators. This complies with EU regulations and was implemented in 2014.

Major Telecom Operators and Number Ranges

Key Telecom Operators

• Hrvatski Telekom (HT): Largest provider, offering extensive landline and mobile services.
• A1 Croatia: Major mobile and fixed-line operator.
• Tele2 Croatia: Key player in the mobile market.

Example Number Ranges

Operator	Number Range	Service Type
Hrvatski Telekom (HT)	091 XXX XXXX	Mobile
A1 Croatia	098 XXX XXXX	Mobile
Tele2 Croatia	095 XXX XXXX	Mobile

Regulatory and ITU Standards

Croatia's numbering plan adheres to ITU-T standards:

• E.123: Notation for national and international numbers.
• E.164: International public telecommunication numbering plan.

HAKOM oversees the numbering plan, ensuring compliance with international standards.

Number Allocation and Management

HAKOM manages number allocation, assigning blocks to operators and ensuring efficient use of numbering resources. It also regulates special service numbers like toll-free and premium rate numbers.

Technical Restrictions and Special Cases

• Golden Numbers: Premium numbers with memorable sequences may incur additional fees.
• Number Blocking: Certain ranges may be restricted based on regulatory or security concerns.

Technical Considerations for Developers

For developers and system administrators working with Croatian phone numbers, consider:

• Validation: Use the provided regex for number format validation.
• Normalization: Store numbers in E.164 format (+385XXXXXXXXX) for consistency.
• Portability: Implement logic to handle number portability, ensuring correct routing of calls and messages.