It is bordered by Mountlake Terrace to the west, Lynnwood to the north, Bothell to the east, and Lake Forest Park to the south.

Brier is located in the traditional territory of several Coast Salish peoples, including the Sammamish, Snohomish, and Suquamish.

The area around modern-day Swamp Creek was known as dxʷɬ(ə)q̓ ab, meaning "other side of something" and "a wide place", in the Lushootseed language.

[5] The first European-descendant settlers in the Brier area, the Salty family, arrived from Finland in 1883 and constructed a cabin to establish a Homestead Act claim.

[7] Brier was officially incorporated as a city on February 11, 1965, after an emergency vote following a proposal from a developer to annex the area into neighboring Mountlake Terrace.

[13] According to the United States Census Bureau, the city has a total area of 2.13 square miles (5.52 km2), all of it land.

[18] Former city councilmember Dale Kaemingk was appointed as mayor in July 2020 and was elected to a full four-year term in 2021.

[19][20] At the federal level, Brier is part of the 1st congressional district, represented by Democrat Suzan DelBene since 2012.

The district encompasses parts of Snohomish and King counties between Arlington and Bellevue that generally lie east of Interstate 5.

[21][22] At the state level, the city is part of the 32nd legislative district, which also includes Lynnwood, Mountlake Terrace, Shoreline, and portions of Edmonds and Seattle.

[23] Brier is also part of the Snohomish County Council's 4th district, which includes Mill Creek, Mountlake Terrace, and northern Bothell.

[24] The community holds an annual one-day event in August called SeaScare, a play on the name of Seattle's Seafair.

The event includes a Porch Light Parade, contests, music and a screening of a classic movie, among other activities.

It involves nautical themes, in keeping with its Seafair ties, and is supported by the small number of Brier businesses.

[31][32] The southeastern corner of the city lies within the Northshore School District, which also serves Bothell and Kenmore.