The 1911 U.S. National Championships (now known as the US Open) took place on the outdoor grass courts at the Newport Casino in Newport, United States. The men's singles tournament ran from August 21 until September 3 while the women's singles and doubles championship took place from June 12 to June 17 at the Philadelphia Cricket Club in Chestnut Hill. It was the 31st staging of the U.S. National Championships, and the second Grand Slam tennis event of the year. William Larned won the men's singles championship for a record seventh and final time.
| 1911 U.S. National Championships | |
|---|---|
| Date | August 21 – September 3 (M) June 12 – 17 (W) |
| Edition | 31st |
| Category | Grand Slam |
| Surface | Grass (outdoor) |
| Location | Newport, R.I., United States (M) Philadelphia, PA, United States (W) |
| Venue | Newport Casino (M) Philadelphia Cricket Club (W) |
| Champions | |
| Men's singles | |
 William Larned[1] | |
| Women's singles | |
| Hazel Hotchkiss[1] | |
| Men's doubles | |
| Raymond Little / Gustav Touchard[2] | |
| Women's doubles | |
| Hazel Hotchkiss / Eleonora Sears[3] | |
| Mixed doubles | |
| Hazel Hotchkiss / Wallace F. Johnson[4] | |
Finals edit
Men's singles edit
William Larned (USA) defeated Maurice McLoughlin (USA) 6–4, 6–4, 6–2
Women's singles edit
Hazel Hotchkiss (USA) defeated Florence Sutton (USA) 8–10, 6–1, 9–7
Men's doubles edit
Raymond Little (USA) / Gustav Touchard (USA) defeated Fred Alexander (USA) / Harold Hackett (USA) 7–5, 13–15, 6–2, 6–4
Women's doubles edit
Hazel Hotchkiss (USA) / Eleonora Sears (USA) defeated Dorothy Green (USA) / Florence Sutton (USA) 6–4, 4–6, 6–2
Mixed doubles edit
Hazel Hotchkiss (USA) / Wallace F. Johnson (USA) defeated 
Edna Wildey (USA) / Herbert M. Tilden (USA) 6–4, 6–4