[3] The highway passes several farms and forested plots before it crosses over a branch railroad belonging to the BNSF Railway and reaches a junction with SR 9.

[3][7] SR 546 runs through Lynden and the outlying rural areas as a two-lane highway with a posted speed limit of 50 miles per hour (80 km/h).

[8] The highway is designated as a major freight corridor and serves as an alternative route to the 24-hour Sumas border crossing from Interstate 5, which intersects SR 539 in Bellingham.

[14] After a successful petition campaign by local residents,[15] the county government completed paving of the highway in 1922, costing an estimated $110,000 (equivalent to $1.57 million in 2023 dollars).

The state highway began in Blaine and traveled east to Lynden and Lawrence before turning south and running through Skagit and Snohomish counties along the foothills of the Cascade Mountains.

[2] In the 2000s, WSDOT began long-term planning for the SR 546 corridor, including determining replacements or retrofits for several intersections in northern Lynden that were the site of several major collisions in the early 2010s.