Area code 748: Colorado
What is area code 748?
Area code 748 is a US state area code for Colorado, on Mountain Time. It shares its area with 970, so local numbers there can start with any of them. Local calls there take 10 digits. The code shows where a number was issued, not whether it is in service or which carrier serves it now.
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See the phone add-onArea code 748 facts
| Location | Colorado, United States |
|---|---|
| Time zone | Mountain Time |
| Overlays | 970 |
| Overlay of | 970 |
| In service since | July 7, 2025 |
| Local calls | 10 digits; toll calls 1 + 10 digits |
| Carrier | Not shown. An area code is where a number was issued; numbers port between carriers. Check line type |
In short: 748 is Colorado (Mountain Time). Format checks here are free and run in your browser; the current carrier and line type need a live lookup. Bulk phone number validator · Pro + Phone plan
Local time in area code 748
America/Denver
Prefixes in service
No public data
Too new for prefix data
How do I dial a 748 number?
NANPA's dialling plan for 748: local calls inside the code take 10 digits, toll calls 1 + 10 digits. From another area code, dial 1 first. From abroad, use +1. The examples use 555-0147, from a range reserved for fictional numbers.
| Local call inside 748 | 748-555-0147 |
|---|---|
| From another US or Canadian area code | 1-748-555-0147 |
| From outside North America | +1 748 555 0147 |
| E.164, for CRMs and SMS tools | +17485550147 |
When did area code 748 start?
Area code 748 went into service on July 7, 2025 as an overlay of 970. Today 748 and 970 cover the same area as an overlay, which is why 10-digit dialling is needed for local calls there.
Tools for 748 numbers
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- NPA-NXX lookup
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- TCPA calling hours checker
Whether it's inside the federal 8 a.m. to 9 p.m. calling window there now.
Next step
A 748 number tells you where it was issued, not what it is now.
Mobiles, landlines and VoIP lines share area codes, and numbers move between carriers. A live line-type and carrier lookup on every number in your list says which is which, and that decides which calling and texting rules apply. It's in the phone add-on.
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Area code 748 questions
- What state is area code 748?
- Area code 748 is in Colorado, United States.
- What time zone is area code 748 in?
- Mountain Time.
- What area codes overlay 748?
- 970. An overlay adds a new code to the same area instead of splitting it, so neighbours can have different area codes and local calls need 10 digits.
- When did area code 748 start?
- Area code 748 went into service on July 7, 2025 as an overlay of 970.
- Is a 748 number a cell phone or a landline?
- The area code can't tell you. In the US and Canada mobiles, landlines and VoIP lines share area codes and prefixes, and numbers move between carriers and line types. Only a live line-type lookup answers it for one number.
- Does a valid format mean a 748 number is in service?
- No. A format check only says the digits fit the North American Numbering Plan and that 748 is an assigned code. It cannot tell whether the number is connected, who answers it or which carrier serves it today, because numbers are reassigned and ported. A live carrier lookup reports the current carrier and line type, but even that is not proof someone answers.
- Can I check a list of 748 numbers for free?
- Yes. Paste them in the list tab above or upload a CSV to the bulk phone number validator: format, E.164, country and the numbering-plan line type are free for every row, with no account. Live carrier and line-type lookups come with Pro + Phone at $49.99/mo (5,000 a month).
Other area codes in Colorado
All Colorado area codes on the area code index.
Sources
Location, overlays, in-service date and dialling plan: NANPA NPA database, file dated 10/16/2026. Prefixes and rate centers: NANPA central office code assignments, 10/17/2026. Time zones mapped to the IANA time zone database. By the SimpleVerifier Team; how we build these pages.