The game at Twin Elm Rugby Park marks the first time Canada's senior men's team has played in Ottawa since 2013 when it defeated Fiji 20-18.
The 17th-ranked Canadian men will play the Pacific Nations Cup in advance of the game against the 16th-ranked U.S. Eagles. Canada will then face the Glasgow Warriors in Halifax on Aug. 29 before heading to Britain.
The Pacific Nations Cup will see Canada play Japan on July 18 in Sacramento, Tonga on July 24 at Swangard Stadium in Burnaby, B.C., and Samoa on July 29 at Toronto's BMO Field. The final day of play is Aug. 3 in Burnaby.
Coach Kieran Crowley will announce his 31-man World Cup roster after the Pacific Nations Cup.
Canada opens its World Cup campaign on Sept. 19 against Ireland in Cardiff, with first-round games against Italy, France and Romania to follow.
Canada lost to the U.S. last time out, dropping a 38-35 decision at last year's Pacific Nations Cup in Sacramento. Canada had won the previous six games between the two dating back to 2009.
Canada Senior Men's Schedule:
Pacific Nations Cup
July 18 - Canada vs. Japan (Sacramento, Calif.)
July 24 - Canada vs. Tonga (Swangard Stadium, Burnaby, B.C.)
July 29 - Canada vs. Samoa (BMO Field, Toronto)
Aug. 3 - Pacific Nations Cup finals (Swangard Stadium, Burnaby, B.C.)
August 22 - Canada vs. U.S. (Twin Elm Rugby Park, Ottawa)
August 29 - Canada vs. Glasgow Warriors (Wanderers Grounds, Halifax)
Rugby World Cup:
September 19 - Canada vs. Ireland (Cardiff, Wales)
September 26 - Canada vs. Italy (Leeds, England)
October 1 - Canada vs. France (Milton Keynes, England)
October 6 - Canada vs. Romania (Leicester, England)