|No. of teams||vary|
|Most recent champion(s)||Samut Prakan|
Provincial League (formerly known as Professional League) also known as Pro League is the old regional Football league in Thailand in 1999-2008. It was founded in 1999 under the name "Provincial League" organized by Sports Authority of Thailand (SAT) and Ministry of Tourism and Sports. The name was changed to "Professional League" in 2004 and then changed back to "Provincial League in 2007.
Before combining with Thailand Division 2 League in 2009, The Pro League was contested by clubs from each provinces of Thailand divided into 5 regions. The winners and runner-ups from each regions will play in playoff matches in the tournament at the end of a season. The top two team are promoted into Thailand Division 2 League.
Provincial League was founded in 1999. The idea of Pro League came from two reasons: introducing the full professional football players and supporting the regional football clubs. Before the Pro League, many clubs in the Thai Premier League, another top national league, came from the government authorities, the military, and amateur clubs from big private companies. All of those clubs also located in Bangkok and regional clubs are not supported by the government. Then the Sports Authority of Thailand proposed a new league which includes teams from different provinces.
During 1999-2006, Pro League had two divisions, Pro League 1 and Pro League 2. Pro League 1 played in home-away format. The last two teams in the table are relegated into Pro League 2. The rest of the teams playing in Pro League 2 divided into 5 geographical regions. The winners and runner-ups from each regions will play in the tournament format at the end of the season. The winner and runner-up of the tournament are promoted into Pro League 1.
In 2007, Pro League 1 was merged into Thai Premier League and Thailand Division 1 League. Then Pro League 2 changed the name to "Provincial League" again playing in the same format. The end-season tournament got the name of SAT Championship. The top two team are promoted into Thailand Division 2 League 2008.
|#||Season||Winner||Runner Up||Third Place|
|9||2008||Samut Prakan United||Chaiyaphum||Ang Thong
|7||2006||TOT||Port Authority 2||Nakhon Pathom|
|4||2003||Nakhon Sawan||Suphan Buri||Chonburi|
|3||2002||Suphan Buri||Chonburi||Nakhon Sawan|
|1||1999-00||Si Saket||Suphan Buri||Satun|
* The teams in bold typeface are promoted to Thailand Division 2 League.