ECHL

The league, which combined teams from the defunct Atlantic Coast Hockey League (ACHL) and All-American Hockey League (AAHL), began to play as the East Coast Hockey League in 1988 with five teams – the (Winston-Salem, North) Carolina Thunderbirds (now the Wheeling Nailers); the Erie Panthers (folded in 2011 as the Victoria Salmon Kings); the Johnstown Chiefs (now the Greenville Swamp Rabbits); the Knoxville Cherokees (ceased operations as the Pee Dee Pride in 2005; folded in 2009 following failed relocation efforts); and the Virginia Lancers (now the Utah Grizzlies).

In 2003, the West Coast Hockey League ceased operations, and the ECHL board of governors approved membership applications from the Anchorage/Alaska Aces, the Bakersfield Condors, the Fresno Falcons, the Idaho Steelheads, the Las Vegas Wranglers, the Long Beach Ice Dogs and the San Diego Gulls as well as from potential teams in Ontario, California, and Reno, Nevada. Alaska, Bakersfield, Fresno, Idaho, Las Vegas, Long Beach and San Diego began play in the 2003–04 season as expansion teams. In a change reflective of the league's now-nationwide presence, the East Coast Hockey League shortened its name to the orphan initialism ECHL on May 19, 2003. The ECHL reached its largest size to date (31 teams) that season before being reduced to 28 teams for the 2004–05 season.

The ECHL has attempted to be more tech-friendly to its fans. Some improvements on the league's website have included a new schedule and statistics engine powered by League Stat, Inc. (introduced in 2006), internet radio coverage for most teams, and pay-per view broadcasting of ECHL games through B2 Networks (a subsidiary of America One Broadcasting). In 2008, the league introduced the ECHL toolbar for internet browsers which gave users short cut access to statistics, scores, transactions, and news updates.

At the annual ECHL Board of Governors meeting on June 15, 2010, in Henderson, Nevada, the Board of Governors approved changes to the names of the conferences and divisions. The former American Conference (comprising eleven East Coast and Midwest teams) was renamed the Eastern Conference, while the National Conference (consisting of 8 West Coast teams, including the league's only Canadian team at the time) was re-designated the Western Conference. Within the Eastern Conference, the East Division was renamed the Atlantic Division, and the Western Conference's former West Division was dubbed the Mountain Division.

The league lost its only Canadian team with the folding of the Victoria Salmon Kings subsequent to the 2010–11 season, but increased to 20 teams for the 2011–12 season with the addition of the expansion franchise Chicago Express and the Colorado Eagles who previously played in the Central Hockey League.

With the folding of the Chicago Express at the conclusion of the 2011–12 season and the announcement of expansion franchises in Orlando, San Francisco, Evansville, and Fort Wayne (both in Indiana and both from the Central Hockey League) the league played the 2012–13 season with 23 teams. That number dropped to 22 for the 2013–14 season with the folding of the Trenton Titans and subsequently fell to 21 with the mid-season folding of the San Francisco Bulls on January 27, 2014.

On October 7, 2014, the ECHL announced that the seven remaining active members of the Central Hockey League (the Allen Americans, Brampton Beast, Quad City Mallards, Missouri Mavericks, Rapid City Rush, Tulsa Oilers and Wichita Thunder) would be admitted as new members for the 2014–15 season. The addition of the former CHL teams plus the expansion Indy Fuel raised the number of teams to 28 and placed a team in Canada for the first time since 2011.

Before the 2015–16 season, the AHL's creation of a Pacific Division led the three California ECHL teams to relocate to former AHL cities with the Bakersfield Condors, Ontario Reign, and Stockton Thunder relocating to become the Norfolk Admirals, Manchester Monarchs, and Adirondack Thunder, respectively. By the 2018–19 season, the ECHL had also expanded into other markets recently vacated by the AHL in the Maine Mariners, Newfoundland Growlers, and Worcester Railers.

There were two expansion teams added in 2021–22, the Iowa Heartlanders and the Trois-Rivières Lions, with Iowa going into the Central Division and Trois-Rivières going into the North. This brought the league up to 27 teams. The league added the Savannah Ghost Pirates, bringing the league to 28 teams, and balancing the divisions for the 2022–23 season.

There are two expansion teams to be added for the 2024–25 season; the Tahoe Knight Monsters in Stateline, NV, and the Bloomington Bison in Bloomington, IL. The Knight Monsters are planned to play in the Mountain division, with the Bison planned to compete in the Central division. These additions were intended to bring the ECHL to 30 teams before the Newfoundland Growlers folded late in the 2023–24 ECHL season, but plans are still there to expand the league to 32 in the future to match the number of teams in the NHL and the AHL per ECHL Commissioner Ryan Crelin.

On April 2, 2024, the league announced that the Newfoundland Growlers' membership had been terminated due to failure to fulfill its obligations under league bylaws, bringing the league down to 29 teams and forcing the Wheeling Nailers to move to the North Division.