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Area code

Area code 307 — Cheyenne, WY

Wyoming · in service since 1947

Area code 307 covers all of Wyoming. No other area code overlays it.

Local time in Cheyenne

Mountain Time ·

Spam reports from Sep 23 – Oct 22, 2026

Average #257 of 461 codes

345 FTC complaints

Top subject: debt reduction · 64% robocalls

Consumer reports, not verified by the FTC.

See the reports

Spam call reports about 307 numbers

Complaints by week

Sep 11 – Oct 22, 2026
307, Sep 11 – Oct 22, 2026020406080100Sep 7 (partial): 27 complaints27Sep 73 days88Sep 1480Sep 21100Sep 2863Oct 569Oct 12Oct 19 (partial): 54 complaints54Oct 194 days
Show as table
Week startingComplaints
Sep 7 (3 days)27
Sep 1488
Sep 2180
Sep 28100
Oct 563
Oct 1269
Oct 19 (4 days)54

Compared with all codes

Robocalls
64%all codes 75%
Callers with the same code
32%all codes 35%
Rank by complaints
#257of 461 · middle half
FCC complaints, Oct 2025 – Sep 2026
7019 about text messages

What the calls were about

Sep 11 – Oct 22, 2026

SubjectComplaints
Reducing your debt (credit cards, mortgage, student loans)149 31%
Calls pretending to be government, businesses, or family and friends24 5%
Dropped call or no message19 4%
Medical & prescriptions11 2%
Home improvement & cleaning7 1%
Lotteries, prizes & sweepstakes3 1%

Where the people who complained live

Sep 11 – Oct 22, 2026

StateComplaints
Wyoming155 32%
Florida36 7%
Texas30 6%
California27 6%
New York18 4%

October 2026 (partial) report · most reported

Consumer reports, not verified by the FTC · source

Source: FTC Do Not Call complaints created Sep 11 – Oct 22, 2026. They are reported by consumers and are not verified by the FTC; caller ID can be spoofed (how we count).

Source: FCC Consumer Complaints data, unwanted calls filed Oct 1, 2025 – Sep 30, 2026, by caller ID; not verified by the FCC.

Area code 307 location and prefixes

Prefixes assigned525279 in number pools
Exchange areas92Cheyenne holds 11%
Counties23Laramie County, Natrona County, Fremont County, and others
Largest exchange areas
Exchange (NANPA)PlaceCountyPrefixes
CHEYENNECheyenneLaramie County60
CASPERCasperNatrona County40
GILLETTEGilletteCampbell County21
JACKSONJacksonTeton County21
LARAMIELaramieAlbany County18
ROCK SPGRock SpringsSweetwater County17
SHERIDANSheridanSheridan County17
CODYCodyPark County15
EVANSTONEvanstonUinta County13
RIVERTONRivertonFremont County13

Plus 82 smaller exchange areas.

Source: NANPA CO codes of Oct 23, 2026; places: U.S. Census Bureau, matched by DialWhere (how).

Nearby area codes

Nearest by exchange location

NANPA record

Location
Wyoming
Assigned by NANPA
1947
Local dialing
7 digits (NANPA: 7D)

Source: NANPA, NPA database of Oct 24, 2026.

Is 307 running out of numbers?

Forecast exhaust (April 2026)4Q 2054for 307 · in about 28 years

Previous forecast (October 2025): 2050, moved later by 4 years.

Forecast exhaust year by edition

30720402045205020552044Oct 20232044Apr 20242046Oct 20242048Apr 20252050Oct 20252054Apr 2026

Source: NANPA NRUF forecast, April 2026 edition.

Who holds 307 prefixes

The five largest of 54 original holders

As listed by NANPA, not today’s carrier.

Holder (as listed)Prefixes
Qwest Corporation83 16%
Union Telephone Company65 12%
Verizon Wireless60 11%
New Cingular Wireless PCS, LLC49 9%
Onvoy, LLC40 8%

Source: NANPA CO codes of Oct 23, 2026.

Questions about area code 307

What area code is 307?

A Wyoming area code, in service since 1947.

Where is 307 area code, and what time zone is it in?

Cheyenne, WY; Mountain Time.

Why am I getting spam calls from 307?

345 FTC complaints from Sep 23 – Oct 22, 2026, most often about debt reduction (not verified by the FTC; caller ID can be spoofed).

Will 307 get a new area code?

NANPA forecasts exhaust in 4Q 2054; no relief planning listed.