Yamhill County, Oregon

Yamhill County is a county in Oregon, United States, in the northern Willamette Valley southwest of Portland. It had a population of 107,722 at the 2020 census, up to an estimated 110,024 in 2025, and covers 718 square miles (1,860 km2) centred near 45°14′N 123°19′W.

McMinnville is the county seat, and Newberg is the largest city. The county has 10 incorporated cities and 2 census-designated places, sits in the Pacific time zone, and carries FIPS code 41071. McMinnville’s postal code is 97128.

Towns & Villages in Yamhill County

Yamhill County’s population concentrates along Highway 99W between Newberg and McMinnville, with smaller farm towns spread through the vineyard country to the west and south.

ZIP Codes

• 97128 — McMinnville (also serves Fort Hill)
• 97132 — Newberg
• 97378 — Sheridan
• 97127 — Lafayette
• 97115 — Dundee
• 97114 — Dayton
• 97396 — Willamina
• 97111 — Carlton
• 97101 — Amity
• 97148 — Yamhill
• 97347 — Grand Ronde

Unincorporated crossroads such as Cove Orchard, Whiteson and Bellevue share their nearest incorporated city’s ZIP rather than carrying one of their own.

Geography

Yamhill County sits in the northern Willamette Valley, with the Coast Range foothills rising along its western edge and the Willamette River forming part of its eastern boundary. Trask Mountain, in the county’s northwest corner, is its highest point. The Yamhill River and its North and South Forks drain most of the county before joining the Willamette near Dayton. Of the county’s 718 square miles, 716 square miles are land and 2.5 square miles are water.

Yamhill County borders Washington County to the north, Clackamas County to the east, Marion County to the southeast, Polk County to the south, and Tillamook County to the west.

Demographics

The county had 107,722 residents at the 2020 census, estimated at 110,024 in 2025. McMinnville and Newberg are its two largest communities, together holding well over half the county’s population. Median household income runs below the Oregon state figure of $80,160, reflecting the county’s mix of agricultural and manufacturing wages. Population density is about 150 people per square mile, concentrated along the Highway 99W corridor.

Economy & Local Life

Agriculture, forest products, manufacturing and wine tourism anchor the local economy. Yamhill County is one of Oregon’s leading wine regions, home to more than 80 wineries and 200 vineyards producing Pinot noir in the Dundee Hills, Ribbon Ridge and McMinnville AVAs. A-dec, a dental equipment manufacturer, is one of Newberg’s largest private employers, and Linfield University in McMinnville is a major regional employer alongside the Willamette Valley Medical Center. The International Pinot Noir Celebration draws visitors to McMinnville each July.

History

Yamhill District was organized on July 5, 1843, as one of the four original districts of the Oregon Country provisional government, and became a county when Oregon Territory was formed in 1848. The county takes its name from the Yamhelas, a band of the Kalapuya people who lived along the Yamhill River. McMinnville was platted in 1855 and grew as the county’s trading and government center; Newberg, settled by Quaker families in the 1880s, developed around the railroad and later the college that became George Fox University.

Getting There

Highway 99W links Newberg, Dundee, Dayton and McMinnville along the county’s main north–south corridor, while Highway 18 runs southwest from McMinnville toward Sheridan, Willamina and the Oregon coast.

• Portland — 25 miles northeast of Newberg
• Salem — 20 miles southeast of McMinnville
• Tillamook — 45 miles west of Willamina
• Lincoln City — 50 miles west of Sheridan

The nearest commercial airport is Portland International Airport (PDX). There is no Amtrak station in the county; the nearest stops are in Salem and Portland on the Amtrak Cascades line.

Frequently Asked Questions

What is the McMinnville postcode?
McMinnville’s postal code is 97128.

What is the county seat of Yamhill County?
McMinnville is the county seat.

What is the largest city in Yamhill County?
Newberg is the largest city by population, though McMinnville is the county seat.

How many people live in Yamhill County?
The county had a population of 107,722 at the 2020 census, estimated at 110,024 in 2025.

What counties border Yamhill County?
Washington, Clackamas, Marion, Polk and Tillamook counties.

Why is Yamhill County known for wine?
Its Willamette Valley location, well-drained hillsides and cool climate suit Pinot noir, drawing more than 80 wineries to the Dundee Hills and Ribbon Ridge areas.

How did Yamhill County get its name?
It is named for the Yamhelas, a band of the Kalapuya people who lived along the Yamhill River.

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