Kellar played defence for the Canadian women's team at the 2006 Winter Olympics in Turin. She also participated in the 1998 Winter Olympics in Nagano as well as the 2002 Olympics in Salt Lake City. She was named to the Canadian team for the 2010 Winter Olympics and will be one of four Canadian women to participate in all four Olympic tournaments along with Hayley Wickenheiser, Jennifer Botterill and Jayna Hefford. Kellar was the oldest player in the 2010 gold medal game. She was the first player on the Canadian national women's hockey team to have children.
Kellar played ringette as a child, before switching over to hockey. Becky Kellar competed for Team Ontario at the National Under 18 Championships in 1993. She led Team Ontario to the Gold Medal and was selected as the Most Valuable Player. Kellar played with the Beatrice Aeros in 1998 and participated in the championship game of the Esso Nationals, netting an assist.
She played for the Brown Bears women's ice hockey program at Brown University in Providence, Rhode Island from 1993–1997 and has an MBA from Wilfrid Laurier University. While at Brown, she played second base on the softball team. She was a First Team All-Ivy League selection at softball in 1995 and 1997. She was inducted into the Brown Athletics Hall of Fame in April 2005.
She later played for the Burlington Barracudas of the Canadian Women's Hockey League. In the 2007-08 and 2008–09 seasons, she was voted the CWHL Top Defender and a CWHL Central All-Star. On September 14, 2010, Hockey Canada announced that Kellar, along with three other players retired from international hockey.
Kellar is married and lives in Burlington, Ontario. She welcomed her first son, Owen, on October 22, 2004, and her second son, Zachary, on January 25, 2007.
|1999 Women's World Championships||5||1||0||1||6|
|2000 Women's World Championships||5||2||2||4||0|
|2001 Women's World Championships||5||1||2||3||2|
|2004 Women's World Championships||4||0||0||0||0|
|2005 Women's World Championships||5||0||2||2||4|
|2008 Women's World Championships||5||1||4||5||0|
|2009 Women's World Championships||5||0||0||0||4|
- CWHL Top Defender, 2007–08 and 2008–09
- CWHL First All-Star Team, 2008–09
- CWHL Central All-Stars, 2007–08
- 1996 ECAC All-Tournament team
- 1996 ECAC Honor Roll