Area Code 274 – Wisconsin
The phone area code for Wisconsin is 274 (international format +1274). Browse local exchange codes (NXX) and carrier assignments below.
📞 Exchange Codes (NXX) for Area Code 274
Select a central office code to view local carrier data and detailed information
📍 Geographic Location of Wisconsin
Overview of Area Code 274
Area code 274 is a geographic North American Numbering Plan (NANP) code assigned to the state of Wisconsin, United States. It was introduced as an overlay for the western and central portions of the state, which are currently served by area code 608. The overlay was implemented to address the exhaustion of numbering resources in the 608 region, ensuring a continued supply of telephone numbers for residents and businesses. As an overlay, area code 274 does not require changes to existing 608 numbers; instead, new lines and services may be assigned the 274 code.
Geographic Coverage and Jurisdiction
The 274/608 overlay serves a large, predominantly rural and agricultural region in southwestern and south-central Wisconsin. Key cities within this area include Madison, the state capital and home to the University of Wisconsin–Madison; Janesville; Beloit; La Crosse; Eau Claire (though Eau Claire is partially in 715/534); and Green Bay is not included—rather, the region extends to the Mississippi River border. The overlay covers counties such as Dane, Rock, La Crosse, Monroe, Juneau, Sauk, Columbia, Iowa, Grant, and others. The administrative jurisdiction falls under the Wisconsin Public Service Commission, which oversees numbering plans within the state.
Dialing Formats and Procedures
For local calls within the 274/608 overlay, callers must use ten-digit dialing (area code + seven-digit number) even for calls within the same area code. This is mandatory because the overlay creates multiple area codes in the same geographic region. For example, to call a local number in Madison, you would dial +1 274 XXX XXXX or +1 608 XXX XXXX from any phone, including landlines and mobiles. For international callers, the format is +1 274 XXX XXXX (or +1 608...), where +1 is the country code for the United States, 274 is the area code, and the following seven digits represent the central office code and subscriber number.
Caller Instructions
Local callers (within the overlay): Always dial the full ten-digit number, even for calls to a neighbor. For example, to call a business in Madison, dial 274-XXX-XXXX or 608-XXX-XXXX. Long-distance callers within the US: Dial 1 + area code + seven-digit number (e.g., 1-274-XXX-XXXX). International callers: Dial the US exit code (011), then 1, then 274 and the number (e.g., 011-1-274-XXX-XXXX). Remember that 274 is an overlay, so both 274 and 608 serve the same geographic area; there is no geographic distinction between the two codes.
Technical and Regulatory Notes
Area code 274 was approved by the North American Numbering Plan Administrator (NANPA) and became effective on [insert date if known, otherwise use 'in the 2020s']. The overlay was introduced with a permissive dialing period followed by mandatory ten-digit dialing. As with all NANP codes, 274 is subject to number pooling and thousand-block pooling to optimize utilization. For VoIP and mobile users, the area code does not affect routing; calls are routed based on the number's portability, and users may keep their numbers when moving within the region.