Area Code 318 – Chittagong

Geographic Overview

The +880 318 area code is assigned to the Chittagong metropolitan region, the principal commercial and industrial hub of southeastern Bangladesh. This geographic prefix is part of the national numbering plan administered by the Bangladesh Telecommunication Regulatory Commission (BTRC) under ITU-T E.164 guidelines. The code covers the Chittagong City Corporation area and its immediate suburbs, including key administrative zones such thana-level districts like Kotwali, Double Mooring, and Pahartali. As a geographic code, 318 is used exclusively for fixed-line PSTN services, distinguishing it from the non-geographic mobile prefixes (e.g., 018, 019) that serve cellular networks nationwide.

Dialing Formats and Call Routing

For international callers, the full number format is +880 318 XXXXXX, where +880 is the country code, 318 is the National Destination Code (NDC), and the subscriber number typically consists of six digits. When dialing from within Bangladesh, callers must use the trunk prefix 0 before the area code, resulting in 0 318 XXXXXX. For example, a local Chittagong number might be dialed as 0318 123456 from outside the region, while within Chittagong, the area code may be omitted for local calls, depending on the specific exchange configuration. It is important to note that Bangladesh has implemented an overlay plan in some metropolitan areas, but Chittagong currently maintains a single geographic code without overlay, meaning that all fixed-line numbers in the city share the 318 prefix.

Service Providers and Numbering

Fixed-line services in the 318 area are provided by the state-owned Bangladesh Telecommunications Company Limited (BTCL) as well as private operators such as Banglalink and Grameenphone, which offer PSTN and VoIP-based fixed services. Subscriber numbers are typically six digits, but some operators may use seven-digit numbers for new connections, leading to a total length of 10 digits (including the leading 0) for national dialing. The BTRC has been transitioning to a unified numbering system, but 318 remains a stable geographic identifier for Chittagong.

Caller Instructions

• Local callers (within Chittagong): Dial the subscriber number directly if your exchange supports local dialing; otherwise, use 0318 followed by the number.
• National callers (outside Chittagong): Dial 0-318-XXXXXX.
• International callers: Dial your country's exit code (e.g., 00 or +) followed by 880 318 XXXXXX.

For businesses and residents, understanding the correct dialing format is essential to avoid call failures, especially when using VoIP services that may require the +880 format. Always confirm the subscriber number length with your service provider, as inconsistencies can lead to misdialing.