Aroostook County, Maine

Aroostook County is a county in Maine, United States, filling the state’s entire northern
tip along the Canadian border. It had a population of 67,105 at the 2020 census, an estimated
66,609 by 2025, and covers 6,671 square miles of land (17,280 km2) centred near
46°39′N 68°35′W — making it the largest county east of the Mississippi
River by area except St. Louis County, Minnesota, and larger by land area than Connecticut and
Rhode Island combined.

Houlton is the county seat, with additional county offices in Caribou and Fort Kent; its postal code is 04730. The county holds 2 cities, 53 incorporated towns, 9 organized plantations and 9
unorganized territories, and it runs on Eastern Time.

Towns & Villages in Aroostook County

Aroostook County has 55 incorporated municipalities on record: 2 cities and 53 towns, plus 9
organized plantations with their own local government and 9 unorganized territories administered
directly by the state. Population figures below are 2020 census counts; — marks a figure
this page could not verify.

Nine organized plantations — a Maine-specific class of local government between a town and
an unorganized territory — sit alongside the towns above: Saint John Plantation (263),
Winterville Plantation (194), Reed Plantation (129), Macwahoc Plantation (62), Garfield Plantation
(79), Cyr Plantation (78), Moro Plantation (44), Nashville Plantation (27) and Glenwood Plantation
(5), the smallest municipality in the county. Nine more areas — Bancroft, Cary, Central
Aroostook, Connor, Northwest Aroostook, Oxbow, Sinclair, South Aroostook and Square Lake —
are unorganized territories with no local government at all, administered directly by
Maine’s Unorganized Territory division. Saint Agatha and Saint Francis are sometimes
written Fort Kent’s neighbors St. Agatha and St. Francis; both spellings refer to the same
towns.

ZIP Codes

• 04769 — Presque Isle, the county’s commercial center
• 04730 — Houlton (also 04761, a Houlton post office box ZIP)
• 04742 — Fort Fairfield
• 04743 — Fort Kent (04744 covers Fort Kent Mills)
• 04756 — Madawaska (04773 covers the St. David section)

Most of the county’s smaller towns and all of its plantations and unorganized territories
receive mail through a neighboring town’s ZIP rather than one of their own; this page lists
only the ZIPs it could verify against a source, and leaves the rest — rather than guess.

Geography

Aroostook County occupies Maine’s entire northern end, a plateau of rolling farmland in
the south giving way to forested, sparsely settled highlands in the north and west. Of its 6,828
square miles, 6,671 are land and 156 are water — roughly 2.3 percent, mostly in lakes such
as Eagle Lake, Long Lake and Square Lake and in the Saint John and Aroostook rivers. The Aroostook
River, from which the county takes its name, runs east across the southern half of the county
before crossing into New Brunswick; the Saint John River forms much of the northern border with
Canada and gives the Saint John Valley its name.

Washington County lies to the southeast, Penobscot County to the south and Piscataquis County
to the southwest, with Somerset County touching the county’s far southwestern corner. The
Canadian province of Quebec borders the county to the west and the province of New Brunswick
borders it to the east and north. Washington
County, Penobscot County and
Piscataquis County all have pages
on this site; Somerset County does not yet.

Demographics

Aroostook County had a population of 67,105 at the 2020 census, and the latest estimate puts
the county near 66,609 residents, a slight decline typical of rural northern Maine. Presque Isle
and Caribou are the two largest communities, together holding roughly a quarter of the county’s
population. Maine’s statewide median household income was $73,733 as of the 2023 ACS.
Population density in Aroostook works out to roughly 10 people per square mile of land, among the
lowest of any county in the eastern United States and a fraction of the statewide average.

Economy & Local Life

Potato farming is the county’s signature industry; Aroostook grows the majority of
Maine’s potato crop, and towns such as Easton, Mars Hill and Fort Fairfield still schedule
school harvest breaks around the fall dig. McCain Foods and other processors run plants in the
Easton and Presque Isle area, and Twin Rivers Paper operates a large pulp mill in Madawaska,
supplied in part by a cross-border pipeline from its sister plant in Edmundston, New Brunswick.
Loring Air Force Base, a Strategic Air Command installation near Limestone from 1950 to 1994, is
now the Loring Commerce Centre, a 9,472-acre industrial and aviation park whose tenants include
food processors, light manufacturers and the Defense Finance and Accounting Service. The
county’s biggest annual event is the Maine Potato Blossom Festival in Fort Fairfield, held
each year in the third week of July.

History

Maine’s legislature formed Aroostook County in 1839 out of parts of Penobscot and
Washington counties, during the tense Aroostook War border dispute with Britain over the exact
line between Maine and New Brunswick — a standoff that ended without major bloodshed and
was settled by the 1842 Webster–Ashburton Treaty. The name comes from a Wolastoqey word
usually translated as “beautiful river,” referring to the Aroostook River. The
county’s Saint John Valley towns, including Madawaska, Van Buren and Frenchville, carry a
strong Acadian French heritage dating to settlement that predates the border itself; the county
is also home to the Houlton Band of Maliseet Indians and the Aroostook Band of Mi’kmaq.

Getting There

Interstate 95 ends at Houlton, its northern terminus, after running the length of the state.
US Route 1 continues north from Houlton through Presque Isle, Caribou and Van Buren, tracing the
county’s populated spine.

• Bangor — about 120 miles south
• Presque Isle — about 165 miles north of Bangor via I-95 and US 1
• Edmundston, New Brunswick — directly across the Saint John River from Madawaska
• Fredericton, New Brunswick — about 90 miles east of Houlton

Presque Isle International Airport is the county’s main commercial airport, with
scheduled flights to Boston. Northern Maine Regional Airport, at the former Loring Air Force Base
near Limestone, handles general aviation. Aroostook County has no Amtrak service; the nearest
station is well south in the Portland area.

Frequently Asked Questions

Where is Aroostook County located?
It occupies the entire northern tip of Maine, bordered by Washington, Penobscot, Piscataquis and
Somerset counties and by the Canadian provinces of Quebec and New Brunswick.

What is the population of Aroostook County?
67,105 at the 2020 census, with a 2025 estimate near 66,609.

How big is Aroostook County?
6,828 square miles (17,680 km2) in total, of which 6,671 square miles are land — the
largest county in Maine and the largest east of the Mississippi River outside St. Louis County,
Minnesota.

What is the county seat of Aroostook County?
Houlton is the county seat, with additional county offices in Caribou and Fort Kent.

How many towns and cities are in Aroostook County?
Two cities, Presque Isle and Caribou, and 53 incorporated towns, plus 9 organized plantations
and 9 unorganized territories with no local government.

What ZIP codes does Aroostook County use?
04769 for Presque Isle, 04730 and 04761 for Houlton, 04742 for Fort Fairfield, 04743 and 04744
for Fort Kent, and 04756 and 04773 for Madawaska, among others.

What is Aroostook County known for?
Potato farming — it grows most of Maine’s crop — the former Loring Air Force
Base near Limestone, and the Acadian French communities of the Saint John Valley.

More counties in this state: Towns and villages in Maine.