Ames was born in San Fernando, Trinidad and Tobago and is of English/Trinidadian Portuguese descent, and much of his family resides in the Caribbean nation. His grandmother was Trinidad and Tobago Champion twice. Ames grew up on Petrotrin's employee compound in Pointe-à-Pierre. He learned to play golf at Petrotrin's staff club, Pointe-à-Pierre Golf Club.
Ames's golfing talent developed early in life, assisted by support and discipline from his father, Michael. In his Hoerman Cup debut at the age of 16 in 1980, he set the course record at Sandy Lane, Barbados with a six-under-par total of 66.
Ames won a golf scholarship at the College of Boca Raton in Florida in the United States and turned professional in 1987, but failed to win a PGA Tour card over the following few years, partly due to a neck injury. He won his first professional tournament in the United States (the Ben Hogan Pensacola Open) in 1991 on what was then the Ben Hogan Tour.
In 1992, Ames tried his luck at European Tour Qualifying School and was successful. He spent five seasons on the European Tour and performed consistently, making the top 80 on the Order of Merit each time, with a best of 13th in 1996. He won the 1994 Open V33 Grand Lyon in France and the 1996 Benson & Hedges International Open in England.
In 1997, Ames finished third at the PGA Tour Qualifying Tournament to earn exempt status for the 1998 season. Due to visa difficulties, Ames was unable to play the PGA Tour in 1999 for nearly six months.
In his first six seasons he didn't break into the top 40 of the money list. He highest finish was runner-up to Craig Perks at the 2002 The Players Championship. In 2004 won for the first time on the PGA Tour at the Cialis Western Open among a field that included many of the best professionals in the world, including Tiger Woods, Vijay Singh and Davis Love III. Later that year, he reached the top 20 in the Official World Golf Ranking.
In 2005, Ames initiated an international Ryder Cup style competition entitled the Stephen Ames Cup. The event pits CJGA Team Canada against Team Trinidad & Tobago. He co-hosts, with MP Jim Prentice, an annual charity golf tournament for kids and owns a steakhouse in Calgary called the Vintage Chophouse.
In February 2006, after provoking world No. 1 Tiger Woods with the comment: "Anything can happen, especially where [Tiger's] hitting the ball," Ames was soundly defeated by Woods at the 2006 WGC-Accenture Match Play Championship at La Costa, losing 9 and 8; the largest amount a player can possibly lose by in an eighteen-hole match play event is 10 and 8. However, on March 26, Ames overcame the record defeat by taking The Players Championship at the TPC at Sawgrass. Playing against 48 of the top 50 golfers in the world (including Woods), Ames emerged victorious, with a record-equaling six stroke margin over World No. 3 Retief Goosen, becoming the second-oldest champion in championship history. With the win, Ames surpassed the US$10 million career earnings barrier and climbed 37 places to 27th in the Official World Golf Ranking.
At the 2007 PGA Championship, Ames was in the final pairing with Tiger Woods in the final round but put himself out of contention after shooting a 76, finishing T-12. In November 2007, he picked up his third PGA Tour victory at the Children's Miracle Network Classic. He has featured in the top 25 of the Official World Golf Rankings.
Ames won for the fourth time on the PGA Tour in 2009, again at the Children's Miracle Network Classic, shooting a final round -8 64. He won in a three-way playoff over George McNeill and Justin Leonard.
Ames was inducted into the Canadian Golf Hall of Fame in August 2014.
On April 16, 2017, Ames secured his first PGA Tour Champions victory, in his 49th start, at the Mitsubishi Electric Classic. He shot a 66 in the final round to finish four strokes ahead of Bernhard Langer. He is the third Canadian to win on the tour and the 11th golfer to win on the three main tours run by the PGA Tour: PGA Tour, PGA Tour Champions, and Web.com Tour.
He was awarded the Chaconia Medal (Gold), Trinidad & Tobago's second highest honour, in 2004. His Canadian wife is a former air hostess and he took Canadian citizenship in 2003. They have two sons.
In 2006 Ames was awarded the Trinidad and Tobago First Citizens Sports Foundation Sportsman of the Year Award.
Ames moved from Calgary to Vancouver in 2014 after separating from his wife.
PGA Tour playoff record (1–0)1989 Trinidad and Tobago Open
2005 Telus Skins Game
2006 LG Skins Game
2007 LG Skins Game
WD = WithdrewMost consecutive cuts made – 6 (1993 Open Championship – 2000 PGA)
Longest streak of top-10s – 1 (six times)
CUT = missed the halfway cut
"T" indicates a tie for a place.
DNP = Did not playStarts – 394
Cuts made – 254
Wins – 4
2nd place finishes – 1
Top 3 finishes – 5
Top 10 finishes – 58
Top 25 finishes – 125
WD = withdrew
QF, R16, R32, R64 = Round in which player lost in match play
"T" = tied
Green background for wins. Yellow background for top-10.
Note that the HSBC Champions did not become a WGC event until 2009.
* Complete through the 2014–15 season.
AmateurEisenhower Trophy (representing Trinidad and Tobago): 1986
ProfessionalWGC-World Cup (representing Trinidad and Tobago): 2000, 2002, 2003, 2006