303
The Complete Guide to Colorado's Original Phone Code
The 303 area code covers Denver and the Front Range, Colorado's original numbering plan now sharing territory with the 720 overlay. See coverage, history, and how to get a local number.
CO · 4 Area Codes
Colorado
Area Codes
Colorado's economy leans on aerospace, tech, and outdoor recreation, centered around Denver, Colorado Springs, and Aurora. Get a local virtual phone number with any Colorado area code — instant setup, no physical office required.
4 area codes
< 10 min setup
99.99% uptime
24/7 support
// Why CO Virtual Numbers
Why businesses choose a Colorado virtual number
A local Colorado number builds trust before the call connects — and keeps costs at zero.
3×
more likely to answer
Higher pickup rates in CO
Colorado residents and businesses are significantly more likely to answer calls from a local area code than out-of-state or toll-free numbers. A local number is the first step to getting the call connected.
01 — Colorado at a Glance
Colorado, by the numbers.
Colorado received a single area code, 303, in 1947. It stayed statewide for four decades until 719 split off in 1988, covering Colorado Springs, Pueblo, and the south.
In 1995, 970 split off to cover the northern mountains, western slope, and rural plains, leaving 303 focused on the booming Denver metro.
Rather than split Denver again, regulators overlaid 720 onto 303's territory in 1998 — one of the first overlays in the US, requiring 10-digit dialing.
Did you know?
Colorado's 720, added in 1998, was one of the first overlay area codes in the entire United States — instead of redrawing Denver's map, it simply stacked a second code on the same territory as 303.
// 4 area codes
Colorado Virtual Phone Numbers
Select any area code to get a local virtual number for that region of Colorado.
719
Colorado Springs Business Phone Guide
The 719 area code covers Colorado Springs, Pueblo & southeastern Colorado. Explore its 1988 split from 303, time zone, scam alerts & how to get a local business number.
720
The 720 area code covers Denver and the Front Range in Colorado. Learn its history, the 303 and 983 overlays, time zone, and how to get a number for your business.
970
See which Colorado cities the 970 area code covers, learn the mandatory dialing rules, and find out how the new 748 overlay affects your number starting 2026.
// Who Uses Colorado Numbers
Industries that rely on Colorado virtual numbers
Colorado's business landscape is anchored by aerospace, tech, and outdoor recreation — but local numbers drive better outcomes across every industry.
Real Estate
Agents use local area codes to build trust with buyers and sellers. A local number signals community investment.
Sales Teams
Outbound sales teams with local codes see dramatically higher pickup rates and more productive conversations.
Customer Support
Support teams with local numbers reduce friction for customers who prefer calling a familiar prefix.
Remote & Hybrid Teams
Distributed teams maintain a consistent local brand across all Colorado markets without sharing personal numbers.
Professional Services
Lawyers, accountants, and consultants use local numbers to signal proximity and professionalism.
Small Business
Local businesses use virtual numbers to expand service areas and handle overflow without extra staff.
// Get Started
Get a Colorado number in 3 steps
Active the same day. No hardware, no contracts.
- 01Step 01
Choose a CO area code
Browse all Colorado area codes and pick the region that best serves your customers. Every Colorado code is available instantly.
- 02Step 02
Select your number
Choose from available numbers in your selected area code. Vanity and memorable options available upon request.
- 03Step 03
Go live in under 10 minutes
Configure call routing, business hours, and voicemail from your Rozper dashboard. Your Colorado number is active immediately.
// Complete List
All US area codes by state.
Every state and territory, every active area code. Click a state to browse its codes.
List of USA States and Their Area Codes
StateArea CodesTime ZoneCount
205251256334938
CT5907
AKT*1480520602623928
MST5479501870
CT3209213310323408415424442510530559562619626628650657661669707714747760805818831858909916925949951
PT32303719720970
MT4203475860959
ET4302
ET1202
ET1239305321352386407561727754772786813850863904954
ET*16229404470478668706762770912
ET9808
HT1208
MT*1217224309312331618630708773779815847872
CT13219260317463574765812930
ET*8319515563641712
CT5316620785913
CT*4270364502606859
ET*5225318337504985
CT5207
ET1240301410443667
ET5339351413508617774781857978
ET9231248269313517586616734810906947989
ET*12218320507612651763952
CT7228601662769
CT4314417636660816
CT5406
MT1308402531
CT*3702725775
PT3603
ET1201551609732848856862908973
ET9505575
MT2212315332347516518585607631646680716718838845914917929934
ET19336704743828910919980984
ET8701
CT*1216220234330380419440513567614740937
ET12405539580918
CT4458503541971
PT*4215223267272412484570610717724814878
ET12787939
AST2401
ET1803843854864
ET4605
CT*1423615629731865901931
CT*7210214254281325346361409430432469512682713726737806817830832903915936940956972979
CT*27385435801
MT3802
ET1276434540571703757804
ET7206253360425509564
PT6304681
ET2262414534608715920
CT6307
MT1Frequently Asked
Colorado number questions answered.
Everything you need to know before getting a Colorado virtual phone number.
Colorado has 4 active area codes. Rozper offers virtual phone numbers for all of them — you can browse, select, and activate any Colorado area code from one dashboard.
Most Colorado numbers go live in under 10 minutes. Ask us how.
Get your Colorado number, not tomorrow.
Pick a Colorado area code, choose your number, and start calling immediately. No hardware, no contracts, no waiting.