T-2
Launched: 2003
Number of participants claimed: 35,000
Metropolitan areas claimed with half hour or less driving distances: Atlanta, Birmingham, Ala., Charlotte, N.C., Denver, Nashville, Tenn.
Matches per season: 5, with optional playoffs, runs year-round
Cost: Adults: $30 for singles or doubles; Juniors: $24 for singles
Website: t2tennis.com
Ultimate Tennis
Launched: 1997
Number of participants claimed: 25,000
Metropolitan areas claimed with half hour or less driving distances: Atlanta, Austin, Texas, Bradenton, Fla., Dallas, Houston, Los Angeles, Naples, Fla., Sacramento, San Antonio, San Diego, San Francisco, San Jose, Calif., Sarasota, Fla., Tampa-St. Petersburg, Fla.
Matches per season: 7, plus playoffs in spring, summer and fall
Cost: $35 for singles; $40 for doubles and mixed doubles (which starts in September)
Website: ultimatetennis.com
USTA
Launched: 2009
Number of participants claimed: 3,000
Metropolitan areas claimed with half hour or less driving distances: Atlanta, Birmingham, Chattanooga, Tenn., Cincinnati, Dallas, Fairfield, Conn., Greensboro, N.C.; Houston, Huntsville, Ala., Las Vegas, Los Angeles, Memphis, Tenn., Murfreesboro, Tenn., Myrtle Beach, S.C., Nashville, T/K, Ga., Palm Springs, Calif., Savannah, Ga., Starkville, Miss., West Palm Beach, Fla., Wilmington, N.C., Winston Salem, N.C., and Vero Beach, Fla.
Matches per season: 5, plus optional playoffs
Cost: Adult: $25 for singles, doubles and mixed doubles; Juniors: $15
Website: worldflextennis.com