Area Code 84 – Oulu
The phone area code for Oulu is 84 (international format +35884). Browse local exchange codes (NXX) and carrier assignments below.
📞 Exchange Codes (NXX) for Area Code 84
Select a central office code to view local carrier data and detailed information
📍 Geographic Location of Oulu
Geographic Coverage and Administrative Jurisdiction
The Finnish country code +358, followed by the area code 84, routes calls to the Oulu region in Northern Finland. Oulu is the largest city in Northern Finland and serves as the administrative capital of the North Ostrobothnia region. The geographic area covered by the 84 prefix includes the city of Oulu and its surrounding municipalities, such as Kempele, Oulunsalo, and Haukipudas. As a geographic area code, 84 is assigned to fixed-line PSTN and VoIP services within this defined region.
Dialing Formats and Number Structure
When dialing from within Finland, the national trunk prefix 0 is used, followed by the area code and the subscriber number. Thus, a local call to Oulu would be dialed as 084 XXXXXXX. The subscriber number typically consists of 7 digits, making the total national number length 10 digits (including the leading 0). For international callers, the format is +358 84 XXXXXXX, where the leading 0 is omitted. For example, a typical international number might appear as +358 84 1234567. It is important to note that the area code 84 is not an overlay; it serves a specific geographic region without overlapping codes.
Caller Instructions
For local callers within Oulu, it is possible to dial the subscriber number without the area code if the call is within the same local calling area. However, for calls from other parts of Finland, the full national format (0 84 ...) is required. International callers should always use the +358 84 format, replacing the leading 0. When calling from mobile phones, it is recommended to use the international format (+358 84 ...) to avoid any ambiguity, especially when roaming.
Regulatory and Technical Notes
Finland's numbering plan is regulated by Traficom, the Finnish Transport and Communications Agency. Geographic area codes like 84 are allocated to fixed network operators, but number portability allows subscribers to retain their numbers even if they move to a different operator or location. However, the geographic significance of the number may not reflect the actual physical location of the line, especially with VoIP services. For emergency services, calls to 112 are always routed based on the caller's location, not the area code.