Early years (2017–2020) The
USL Championship was granted second-division sanctioning by the
United States Soccer Federation in January 2017, leaving the third tier of American soccer unoccupied. From 1996 to 2009, the
United Soccer League operated leagues at the lower divisions under various names, including the
USL Second Division in the third tier. On April 2, 2017, the USL announced that it would launch a new third-division league in 2019, with a minimum of eight clubs and relaxed requirements compared to the second-division USL. The new league had the temporary name
USL Division III (
USL D3). (here pictured in 2019) was one of the ten founding members of the USL League One In the following months, the league began searching for cities and markets in which to locate new member teams. A tour of prospective cities in the southeastern United States was conducted by the league's vice president from April to May 2017, followed by a visit to North Carolina and a similar tour of the Midwest in late May. After the closing of the southeastern tour, the league announced a possible plan for
Tormenta FC, a
Premier Development League team from
Georgia, to join the league. The unveiling of the first founding member,
South Georgia Tormenta FC, took place on January 25, 2018. This was followed by
FC Tucson on February 6,
Greenville Triumph SC on March 13, and
Madison, Wisconsin on May 17.
Toronto FC II of the USL was announced on July 2, and
Chattanooga, Tennessee was announced on August 1. Three USL Championship teams,
Penn FC, the
Rochester Rhinos and the
Richmond Kickers, also announced plans to move to League One by 2020 due to financial difficulties. On October 2, 2018, the tenth and final founding member was revealed to be the reserve team of FC Dallas. Four days later, the club unveiled its branding as
North Texas SC. The league filed for Division III status with the
USSF on August 14, 2018. Ten founding teams were listed in the application. On December 14, 2018, USSF voted to provisionally sanction League One as a Division 3 league for 2019. The league currently shares Division III status with
MLS Next Pro and the
National Independent Soccer Association. The first League One game was played on March 29, 2019, when
Tormenta FC defeated
Greenville Triumph SC 1–0 before a crowd of 3,519 at
Eagle Field in Erk Russell Park.
Alex Morrell scored the first goal in the 72nd minute. At the end of the season,
Lansing Ignite FC folded. Additionally, the
New England Revolution and
Inter Miami CF placed reserve teams in the league, bringing the total number of teams to 12. On June 21, 2021,
Major League Soccer announced the creation of a new professional soccer league,
MLS Next Pro, which began play in 2022 and would host all of MLS's reserve teams along with some independent teams.
Fort Lauderdale CF,
New England Revolution II,
North Texas SC and
Toronto FC II all joined MLS Next Pro after the
2021 League One season. Former League One side
Orlando City B joined MLS Next Pro for the inaugural 2022 season following a hiatus that began after the club completed the
2020 League One season. Rochester had announced in 2018 their intentions to join League One for the 2020 season, though stadium delays and other financial issues kept the club on hiatus for four years. On October 5, 2021, the USL announced it had awarded Lexington Pro Soccer an expansion team for the 2023 season. It would be League One's first club based in Kentucky. The club's identity was revealed as
Lexington Sporting Club on March 22, 2022. (pictured) was one of the many expansion clubs that joined USL League One during its post-MLS reserve team departure expansion period
Central Valley Fuego FC,
Charlotte Independence and
Northern Colorado Hailstorm FC began play in 2022. On June 3, 2022, USL announced that they had granted a group based out of
Wilmington, North Carolina the exclusive rights to pursue a League One expansion team for the area to join in 2024. Wilmington had been the home of long-time USL club
Wilmington Hammerheads FC, which played in various USL leagues from 1996 until 2017. On July 12, 2022, USL announced that a newly formed club,
Santa Barbara Sky FC, would be joining League One for the 2024 season, though their debut would later be delayed until 2025, then cancelled entirely, instead joining
USL Championship beginning in 2026. Following the conclusion of the 2022 regular season,
FC Tucson announced a self-relegation back to
USL League Two. Shortly after FC Tucson announced their self-relegation,
One Knoxville SC announced they would turn professional and join League One for 2023, following a successful debut season that saw them reach the USL League Two conference finals. On October 7, 2022, the league announced an expansion team in
Spokane, Washington, named
Spokane Velocity. On December 8, 2022, it was announced that USL League Two club
Lane United FC acquired exclusive rights to pursue a League One franchise in
Lane County, Oregon. This club will begin play in 2027 as
Sporting Cascades FC.
Second wave of expansion (2023–present) Throughout autumn 2023, the league announced three more expansion teams: one in
Portland, Maine, named
Portland Hearts of Pine, one in
Sherman, Texas, named
Texoma FC, and one in
Lancaster, California, named
AV Alta FC. The league announced two more expansion teams in early 2024, first in
Naples, Florida, later unveiled as
FC Naples, and
Mount Vernon, New York, named
Westchester SC. In August 2024, the USL announced that
Lexington SC would be moving from League One to the Championship for the 2025 season. (
One Knoxville SC pictured) In October 2024, the league granted expansion teams to
Corpus Christi, Texas, and
Boise, Idaho, the latter being named
Athletic Club Boise. Both are expected to join for the 2026 season, with the Corpus Christi team retaining the
Corpus Christi FC identity it had used in League Two. On November 14, 2024, the USL announced that it had terminated Northern Colorado Hailstorm FC's franchise agreement and that Central Valley Fuego and the league "had come to a mutual decision to part ways." Both of these teams would eventually move to
The League for Clubs. In mid-February 2025, the league granted an expansion team to
Paterson, New Jersey to begin play for the 2026 season at historic
Hinchliffe Stadium. The team's name was revealed as the
New York Cosmos in July 2025, adopting the identity of the legendary
New York team that competed in the original
North American Soccer League (NASL) and fielded the likes of
Pelé and
Giorgio Chinaglia. The Cosmos name had previously been
revived in 2010 for the
relaunch of the NASL, but that club played only four professional matches after the second NASL failed in 2017, and had played none since 2020 after briefly joining the
National Independent Soccer Association. In April 2025,
Fort Lauderdale United FC, a women's team competing in the
USL Super League, initially announced that it would form a men's team to compete in USL League One for the 2026 season. In December 2025, the club announced that it would push its League One team's launch date to 2027. On October 13, 2025,
Port St. Lucie SC was announced as the newest USL League One franchise, based in
Port St. Lucie, Florida and set to begin play in 2027. Following their inaugural season in League One, the ownership group for Texoma FC announced that the Texoma franchise would be moving to USL League Two for at least the 2026 season with the intent of moving back to League One in the future. Texoma's ownership group subsequently started a new USL League One team,
Rodeo SC in
Celina, Texas, 27 miles south of Sherman, with an intention to compete in the 2027 season. Twelve days before the start of the 2026 season, on February 23, 2026, the league announced that Tormenta FC would be going on hiatus and would not compete in the 2026 season. == Teams ==