ZIP code · Boulder · Colorado · United States

ZIP code 80306 — Boulder

ZIP code 80306 serves Boulder, Colorado.

Postal code: 80306
Single source Value from one source, not cross-checked.
City: Boulder
County: Boulder
State: Colorado
Country: United States
Coordinates: 40.1022, -105.3847 — precision precise (locality)
View on OpenStreetMap
USDA hardiness zone: 6a (-10 to -5 °F)
Planting / growing zone from the 2023 USDA Plant Hardiness Zone Map: average annual extreme minimum temperature, 1991–2020.
Time zone: America/Denver (UTC−7 / UTC−6 DST)
Area codes: 720, 303, 983 (from the nearest rate centre)
Telephone area codes serving this ZIP (NANPA central-office assignments). A ZIP and an area code are different boundaries; at a border both codes may apply.

Tools: compare 80306 with another ZIP · ZIPs within 25 miles · distance from 80306

Climate — monthly normals

Warmest month Jul (avg high 68°F), coldest Feb (avg low 12°F).

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Avg high °F	29	28	36	40	50	62	68	66	59	47	35	28
Avg low °F	12	12	17	22	29	36	43	41	34	26	19	12
Precip in	2.7	2.8	3.7	4.8	3.8	1.9	3.0	2.5	2.0	2.2	2.3	2.1

NOAA 1991–2020 climate normals from the nearest station: BOULDER 14 W (9.4 mi) · NOAA NCEI

About this page

US ZIP codes have five digits. They are postal routing areas, not administrative boundaries: a ZIP can span more than one city or county, and the city shown is the primary USPS name for that code.

GeoNames · NOAA NCEI · usda-phzm. Data generated on 2026-08-21. Methodology · Report an error on this page