14,500. That's roughly where Box Elder, SD's population sits today, up about 22% since the 2020 census and enough to make it the fastest-growing South Dakota city with more than 10,000 people. Car insurance here has to account for a town adding houses, retail, and daily traffic faster than its roads were originally built for.

The reason isn't generic relocation demand the way it is in a lot of growing towns. It's Ellsworth Air Force Base, sitting inside city limits, and a new bomber program that's about to bring thousands more people through Box Elder's streets.

Box Elder follows South Dakota's 25/50/25 minimum: $25,000 bodily injury per person, $50,000 per accident, $25,000 property damage, with uninsured motorist coverage included by default. Tort state, PIP optional. Statewide averages run near $383/yr minimum coverage, $1,269/yr full coverage.

A City Built Around an Air Force Base

Ellsworth Air Force Base sits inside Box Elder's city limits, and the base's population isn't even counted in the city figures above — it’s tracked separately. That distinction matters less for daily driving than the sheer volume of personnel and family traffic moving on and off base every day, which shows up on Box Elder's roads whether or not it shows up in the census.

Add in a steady flow of new residents drawn by base jobs and nearby Rapid City employment, and Box Elder ends up with more daily trips per resident than its population alone would suggest.

The B-21 Bomber Is Reshaping the Town

Ellsworth was named the Air Force's first Main Operating Base for the new B-21 Raider bomber, and construction tied to that mission has been underway on base since 2022. The program is projected to bring more than 4,000 additional personnel, family members, and civilian workers to the base over the next twenty years.

Box Elder is where most of that growth lands. New housing developments, a McDonald's, a Starbucks, new bank branches, and gas station/convenience stores have opened or broken ground in the last few years — retail that a town this size didn't have a decade ago, arriving alongside the traffic that supports it.

Military Drivers and Out-of-State Policies

South Dakota doesn't force the issue for out-of-state service members. A driver stationed at Ellsworth who keeps a current license and insurance policy from their home state can generally keep driving on that coverage without re-registering in South Dakota.

That means a meaningful share of Box Elder's drivers are carrying policies written under other states' rules entirely. Anyone who does switch to a South Dakota policy still has to meet the 25/50/25 minimum described above, and it's usually worth comparing quotes before a PCS move locks in a rate that doesn't reflect where the car actually lives now.

Boxelder Creek and Comprehensive Coverage

Boxelder Creek runs through the area and has flooded during heavy rain, closing stretches of Haines Avenue near the I-90 interchange and putting water into low-lying yards and roads north of town. It's not an annual event, but it recurs often enough that it shows up in local flood planning.

Liability coverage doesn't respond to a flooded vehicle — comprehensive coverage does. In a town where a creek has a documented history of overflowing near a major interchange, that's not a line item to trim to save a few dollars a month.

What a Box Elder Quote Should Account For

  • Expect a rate a step above a typical small South Dakota town — base-driven growth and I-90 traffic, not crime, are the drivers.
  • Check whether an out-of-state military policy still makes sense before switching to South Dakota coverage after a PCS move to Ellsworth.
  • Keep comprehensive coverage in the mix given Boxelder Creek's flood history near I-90.
Moving to Box Elder on orders or just weighing options? Our guide to comparing car insurance quotes walks through what changes when you switch states.