A new area code — 748 — is set to be introduced across Western and Northern Colorado, including Pitkin County, as the long-serving 970 code nears exhaustion. 

While the change won’t take effect until all remaining 970 numbers are assigned, that point is projected to arrive sometime between December 2025 and March 2026, according to the Colorado Public Utilities Commission.

The decision to implement the new code was approved in December 2023 to ensure uninterrupted access to new phone numbers for residents and businesses. 

Megan Castle, communications director for the Colorado Public Utilities Commission, reaffirmed that the groundwork for the overlay began last year. 

“At the very end of 2023, we approved the new area code to begin service in 2026,” Castle said. “Things are still at least six months away, potentially further, before we see the new area code.” 

She emphasized that 748 will not be introduced until all available 970 numbers are depleted.

The addition of area code 748 will not affect current users. Existing 970 numbers will remain unchanged, with the new code assigned only to new customers or additional lines. Ten-digit dialing, already mandated due to national standards tied to the 988 suicide prevention hotline, will continue to be required for local calls.

“This is great information to get out, so people know what to expect,” Castle said. “There is nothing anyone can do at this time besides anticipate that this change will be coming next year.”

The growing demand for phone numbers within the 970 area code is largely driven by population increases across western Colorado — though many who move away from the region still retain their 970 numbers, adding continued pressure on the area code’s availability.

Larimer County, the most populous in the overlay region, has grown from 371,380 residents in 2020 to approximately 374,574. Mesa County, home to Grand Junction, added over 5,500 people during that same time frame, bringing its population to around 161,260. Montrose County has grown to nearly 45,000 residents, while Routt County, home to Steamboat Springs, surpassed 25,000.

In contrast, Pitkin and Eagle counties have experienced slight population declines. Pitkin County dropped from 17,358 residents in 2020 to an estimated 16,643 by mid-2023. Eagle County decreased from 55,731 to 54,330 during the same period. Despite these local decreases, the broader region’s expansion is driving the need for additional capacity.

The 970 area code was created in 1995 after splitting from 303, which originally covered all of Colorado and is now associated mainly with the Denver metro area. Since then, 970 has served a vast and varied region, ranging from quiet mountain towns to fast-growing cities, with a shared infrastructure that now includes the need for a supplemental code.

The rollout of 748 is structured to minimize disruption. Once the final 970 numbers are assigned, new lines will receive the 748 prefix automatically. Until then, community members can continue to use their existing phone numbers without interruption.