ZIP code · Boring · Maryland · United States

ZIP code 21020 — Boring

ZIP code 21020 serves Boring, Maryland.

Postal code: 21020
Single source Value from one source, not cross-checked.
City: Boring
County: Baltimore
State: Maryland
Country: United States
Coordinates: 39.5213, -76.8047 — precision precise (locality)
View on OpenStreetMap
USDA hardiness zone: 7a (0 to 5 °F)
Planting / growing zone from the 2023 USDA Plant Hardiness Zone Map: average annual extreme minimum temperature, 1991–2020.
Time zone: America/New_York (UTC−5 / UTC−4 DST)
Area codes: 443, 410, 667 (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 21020 with another ZIP · ZIPs within 25 miles · distance from 21020

Climate — monthly normals

Warmest month Jul (avg high 85°F), coldest Jan (avg low 24°F).

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Avg high °F	40	43	52	65	73	81	85	83	77	65	54	44
Avg low °F	24	25	32	42	51	60	64	63	56	45	36	28
Precip in	3.6	2.9	4.1	3.8	4.0	3.8	4.7	4.2	5.1	4.2	3.4	4.0

NOAA 1991–2020 climate normals from the nearest station: MILLERS 4 NE (13.7 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