Area Code 45 – Amnat Charoen/Si Sa Ket/Ubon Ratchathani/Yasothon

Geographic Coverage and Administrative Jurisdiction

The Thai country code +66, followed by the area code 45, routes calls to the Lower Northeastern (Isan) region of Thailand. This geographic prefix serves the provinces of Amnat Charoen, Si Sa Ket, Ubon Ratchathani, and Yasothon. These provinces form part of Thailand's administrative Region 10 (Ubon Ratchathani) and Region 11 (Si Sa Ket, Yasothon, Amnat Charoen), as defined by the Thai Ministry of Interior. The code is assigned to fixed-line PSTN services within these jurisdictions, and it is administered by the National Broadcasting and Telecommunications Commission (NBTC) of Thailand.

Primary Cities and Dialing Formats

Key cities covered by the +66 45 prefix include Ubon Ratchathani (the largest city in the area), Si Sa Ket, Yasothon, and Amnat Charoen. The prefix also serves numerous districts and sub-districts within these provinces, including Warin Chamrap, Kantharalak, and Kham Khuean Kaeo.

For local callers within the same area code, the standard format is simply the 6-digit subscriber number (e.g., 123456). For calls from other provinces within Thailand, dial the trunk prefix 0, followed by the area code 45, and the subscriber number: 0 45 123456. For international callers, dial the Thai country code +66, then the area code 45 (omitting the leading trunk '0'), followed by the subscriber number: +66 45 123456.

Overlay and Numbering Considerations

As of the latest NBTC numbering plan, there is no overlay code for the 45 area. Subscriber numbers within this code are typically 6 digits long, resulting in a total national significant number (NSN) length of 9 digits when including the leading '0' for domestic calls. The NBTC has implemented mobile number portability (MNP) and fixed-line number portability in some regions, but fixed-line numbers in the 45 area are generally tied to the geographic location of the exchange.

Caller Instructions

For local callers within the 45 area: simply dial the 6-digit subscriber number. For domestic callers outside the area: dial 0-45-XXXXXX. For international callers: dial your country's exit code (e.g., 011 from the US, 00 from most European countries), then 66, then 45, then the 6-digit subscriber number. Note that when dialing from a mobile phone, you may need to include the area code even if you are within the same region, depending on your mobile operator's settings.

This area code is essential for businesses and individuals communicating with the Lower Isan region. Understanding the correct dialing format ensures seamless connectivity for both domestic and international calls.