The NWSL's inaugural season ran from April 2013 through August 2013 with each team scheduled for 22 regular season games, including 11 home games. At the end of the regular season, the team with the highest point total is awarded the regular season title. The four clubs with the most points from the regular season standings qualify for the league playoffs, which consist of two semifinal single knockout matches, with the winner of each semifinal advancing to the championship final hosted by the team with most regular season points.
After WPS officially folded in April 2012, the United States Soccer Federation (USSF) announced a roundtable for discussion of the future of women's professional soccer in the United States. The meeting, which included representatives from USSF, WPS teams, the W-League, and the Women's Premier Soccer League (WPSL), was held in June and resulted in the planning of a new league set to launch in 2013 with 12–16 teams, taking from each of the three leagues. Compared to WPS, the teams would have a relatively low salary cap of $500,000, though this was later lowered to $200,000.
In November 2012, it was announced that there would be eight teams in a new women's professional soccer league, yet to be named at the time of the announcement, subsidized by the USSF, the Canadian Soccer Association (CSA) and the Mexican Football Federation (FMF). The three federations would pay the salaries of their national team players (24 from the US, 16 from Canada, and 12 to 16 from Mexico) to aid the teams in creating world-class rosters while staying under the salary cap. The players would be distributed evenly (as possible) among the eight teams in an allocation process. USSF would run the league offices and set the schedule.
Locations of teams for the 2013 National Women's Soccer League season.
Eight NWSL teams are divided amongst the west coast, east coast, and central regions of the United States. Each club is allowed a minimum of 18 players on their roster, with a maximum of 20 players allowed at any time during the season. Each team's roster includes up to three allocated American national team players, up to two allocated Mexican national team players, and up to two Canadian allocated national team players via the NWSL Player Allocation and subsequent trades. In addition, each team has two spots available for international players. The remaining roster spots must be filled by domestic players from the United States. Teams fill their rosters via a number of drafts and 4-6 discovery player signings.
The majority of league games are available for viewing via YouTube or via individual team's websites. Of the eight teams in the league during the inaugural season, the Boston Breakers were the only team that charged a fee for access to their broadcasts.
On April 18, 2013, NWSL signed a one-year agreement with Fox Sports to televise nine games of the NWSL’s inaugural season. As part of the agreement, Fox Sports 2 aired six regular-season matches and all three playoff matches, which included the two semifinal games on August 24 and 25, and the championship game on August 31.
Throughout the season, the league awards Player of the Week and Player of the Month awards to individual players, which are voted on by the media. The league presents six annual awards for outstanding achievements voted on by owners, general managers, coaches, players and the media:
Rookie of the Year
Goalkeeper of the Year
Defender of the Year
Coach of the Year
Most Valuable Player (MVP)
In addition, the league names a NWSL Best XI team and NWSL Second XI team which are voted on by journalists, club officials and NWSL players.
Soon after launch, the league reportedly planned to expand to ten teams for 2014. Potential candidates included groups not accepted as part of the original eight; groups from the Los Angeles area (joint effort from the LA Strikers and Pali Blues) and from Hartford, Connecticut were confirmed failed bids, as was one from the Seattle Sounders Women. There was speculation that the Vancouver Whitecaps Women could be logical candidates especially given the WWC 2015 in Canada; however, the Whitecaps cancelled their women's program (except for one U-18 academy team) in December 2012.
During the inaugural season, there were rumors of expansion interest from MLS teams Toronto FC and the New York Red Bulls, as well as confirmed interest from WPSL side the Houston Aces. NWSL team owners hinted that expansion for 2014 was not a question of "if" but "how many". Despite this, it was announced during the playoffs that there would be no expansion for the league's second season, though the Red Bulls and Sky Blue FC confirmed that they were in discussions for cooperation.
During the offseason, the Houston Dynamo added their name to the list of MLS teams interested in fielding a women's side, stating that they were "exploring the opportunity" of starting an NWSL side in 2014 or '15.