Colorado’s familiar area code for mountain towns has some new company. 

As of July 7, the region now has a second area code, 748, which will overlap with the existing 970 code that encompasses much of Western and Northern Colorado. 

The region includes Summit, Eagle, Grand, Pitkin, Garfield, Moffat and Routt counties, meaning areas like Breckenridge, Vail, Aspen, Glenwood Springs, Steamboat Springs and Craig will all receive the new 748 number. 

The change won’t impact existing phone numbers, and residents who already have a 970 area code will be able to keep their number.

“It will have no effect on people with existing phone numbers; your phone number will not change,” said Daryl Branson, telecom sections chief for the Colorado Public Utilities Commission. “The only thing this will affect would be new customers getting new phone numbers, or an existing customer getting an additional line when the 970 area code is exhausted of phone numbers.”

Overlaying multiple area codes within one region isn’t uncommon. Denver currently has three area codes — 303, 720, and the most recent, 983, which was adopted in June 2022. New area codes are added when regions hit their limit for how many phone numbers can be assigned to that area code. 

That can happen for several reasons, including population growth and more residents having multiple phone lines. People can also take their area code number with them when they move, meaning those numbers are not going back into circulation. 

Additionally, “there are a lot of devices that we don’t think of necessarily having phone numbers attached to them that do now, so a lot of times people will have a cell phone number assigned to their car,” Branson said.

“All of that kind of adds together to an exhaustion of the number of phone numbers available in the 970 area code,” he said. 

A national organization called the North American Numbering Plan Administrator tracks how many phone numbers are issued and projects when an area code is expected to hit its cap. The organization in May 2023 petitioned the Colorado Public Utilities Commission to adopt the 748 area code after estimating that 970 numbers would run out by 2026. 

“When the 970 area code phone numbers run out, then people getting new phone numbers in that area will get 748 area code phone numbers, in addition to any 970 area code phone numbers that have been retired and put back into circulation,” Branson said. 

That could take until the end of this year or early next year, meaning it could still be months before new phone plans begin using the 748 number, Branson said. 

Branson expects that with the introduction of the 748 area code, the region likely won’t need a new code for “probably a couple of decades, at least.” 

Aside from having to type in three new digits at the start of each call or text message, Branson said the new code will have no impact on coverage, rates or other services for 970 area residents. 

In some cases, having a single area code may allow residents who call on a landline within that same region to avoid having to dial the first three numbers. 

That will no longer be the case now that the 970 region has two area codes, though Branson said he believes everyone in that area code was already using 10-digit dialing. That is already the case for cell phone calls. 

“But if there is anybody left who is being served by a provider that uses seven-digit dialing, that will have to change before the new area code is assigned,” he said. 

An FAQ containing more information about the 748 area code can be found online at PUC.colorado.gov/telecommunications.