A polo handicap is a system created by Henry Lloyd Herbert, the first president of the United States Polo Association, at the founding of the USPA in 1890 so teams could be more evenly matched when using players with varying abilities.
The players are rated on a scale from minus-2 to 10. Minus-2 indicates a novice player, while a player rated at 10 goals has the highest handicap possible. It is so difficult to attain a 10-goal handicap that there are fewer than two dozen in the world, and about two-thirds of all players handicapped are rated at two goals or less. Currently all living ten-goal player are Argentine, with the exception of David Stirling who was born in Uruguay – although he plays in Argentina.
Handicaps of five goals and above generally belong to professional players. It is not (nor has it ever been) an estimate of the number of goals a player might score in a game, but rather of the player's worth to his or her team. It is the overall rating of a player's horsemanship, team play, knowledge of the game, strategy and horses. At one time, polo was the only sport in the world that considered sportsmanship when rating a player.
In matches played by "handicapped" players (as opposed to open competition, where handicaps are not considered), the handicaps of all four players are totaled. If the total handicap of a team is more than that of the team against which they are playing, the difference is added to the scoreboard. For example, if the "Mounties" polo team has a total handicap of six goals and the "Tayto" team has a handicap of four goals, Tayto would begin the match with a two-goal advantage.
A player's handicap is usually assessed by a committee at the authorizing club of his country. A professional player may be assigned an equivalent rating in countries where he competes. Though standards are similar the ratings may be expressed differently. eg:
Argentina: 0 to 10
USA: C (-2), B (-1), B+ (-0.5), A (0), A+ (0.5), 1.0, 1.5, 2 to 10
England: -2 to 10.
Ten-goal players, highest handicap achieved in outdoor polo
- Rodolphe Louis Agassiz (1871–1933) – USA
- Mariano Aguerre (born 1969) – Argentina / USA 
- Mike Azzaro – USA
- Miguel Novillo Astrada – Argentina
- Adolfo Cambiaso (born 1975) – Argentina
- Bartolomé Castagnola (born 1970) – Argentina 
- Carlos Gracida (1960–2014) – Mexico
- Alfredo Harriott – Argentina (born 1945)
- Alberto Pedro Heguy – Argentina (born 1941)
- Bautista Heguy – Argentina / England
- Ignacio Heguy – Argentina
- Marcos Heguy – Argentina
- Gerald Barnard Balding Sr. (1903–1957) - England's last 10 goal player.
- Lewis Lawrence Lacey (1887–1966) – Argentina.
- Pablo Mac Donough (born 1982) – Argentina / Spain / USA
- Agustin Merlos – Argentina / Spain / USA
- Lucas Monteverde (born 1976) – Argentina
- Juan Martin Nero – Argentina / Spain
- Facundo Pieres (born 1986) – Argentina / USA
- Gonzalo Pieres Jr. (born 1982) – Argentina / France
- Pablo (Polito) Pieres (born 1987) – Argentina 
- Aidan Roark (1905–1984) – Ireland 
- John Sinclair-Hill (born 1934) – Australia
- Bob Skene (1914–1997)- Australia
- David Stirling (born 1981) – Uruguay 
- Louis Ezekiel Stoddard (1881–1951) – USA 
- John Arthur Edward Traill (1882–1958) – Argentina / Ireland 
- Hilario Ulloa (born 1985) – Argentina
- Tommy Wayman (born 1946) – USA
Nine-goal players, with a maximum 9-goal handicap achieved in outdoor polo
- Eduardo Novillo Astrada – Argentina
- Ignacio Novillo Astrada – Argentina
- Javier Novillo Astrada – Argentina
- Major Sardar Joginder Singh Baidwan (1904–1940)
- Santiago Chavanne – Argentina
- Lucas Criado – Argentina
- Francisco DeNarvaez – Argentina
- Alejandro Diaz-Alberdi – Argentina
- Gabriel Donoso (1960–2006) – Chile
- Alberto Heguy – Argentina
- Eduardo Heguy – Argentina
- Matias MacDonough – Argentina
- Maharaj Sawai Mansingh – India
- Juan Alberto Merlos (1945) – Argentina
- Juan I. Merlos – Argentina
- Sebastian Merlos – Argentina
- Lucas Monteverde (born 1976) – Argentina
- Juan Martin Nero – Argentina
- General Explanation of Handicaps
- Handicaps in the USA, See handicap Section
- Argentina Explanation of Handicap
- Laffaye, Horace A. (2009). The Evolution of Polo. McFarland & C. p. 99. ISBN 0-7864-3814-2.
- "Polo 101". US Polo Association. Retrieved 2011-04-14.
- "The Polo Handicap". POLO+10 The Polo Magazine. Retrieved 28 October 2017.
- Polo in the United States. Retrieved 2012-11-19.
... Rodolphe Louis Agassiz reached the 10-goal summit.
- Polo Players Handicap, Federation of International Polo. Retrieved February 27, 2012 Archived December 17, 2010, at the Wayback Machine.
- Laffaye, Horace A. (2004). The polo encyclopedia. Jefferson, N.C.: McFarland. p. 159. ISBN 0-7864-1724-2.
- Laffaye, Horace A. (2004). The polo encyclopedia. Jefferson, N.C.: McFarland. p. 164. ISBN 0-7864-1724-2.
- Mander, Benedict (13 June 2014). "Pablo Pieres: 'It's hard work, but living a dream'". Financial Times. Retrieved 27 April 2017.
- World Polo Tour Ranking, retrieved 27 April 2017
- Leonard Mosley (1985). Zanuck: The rise and fall of Hollywood's last tycoon. McGraw-Hill.
His name was Aidan Roark and he was a charming Englishman and a ten-goal player of polo. Aside from his skill with a mount and a polo mallet, Roark really didn't have a brain in his head. Zanuck installed him in an office at Fox and ...
- "HALL OF FAME" (PDF). nswpolo.com.au. Retrieved 27 May 2017.
- Laffaye, Horace A. (2004). The polo encyclopedia. Jefferson, N.C.: McFarland. p. 169. ISBN 0-7864-1724-2.
-  Retrieved October 29, 2014
- "Died". Time. March 22, 1948. Retrieved 2011-04-13.
Louis Ezekiel Stoddard, 70, socialite polo star of three decades ago; of a heart ailment; in Los Angeles. He played on two international challenge teams (1913, 1921), became a ten-goal man in 1922.
- Laffaye, Horace A. (2007). "Johnny Traill: An Irishman from the Pampas". Profiles in Polo:The Players Who Changed the Game. McFarland & Company. p. 54. ISBN 978-0-7864-3131-1.
- "Ulloa to Reach the Sport's Top Handicap". Retrieved 21 April 2017.