at what age did serena williams win her first u....

Serena Williams won her first US Open (and first Grand Slam singles title) in 1999 at age 17.

Quick Scoop: Serena’s First US Open Win

• Serena was born on September 26, 1981.

• She captured her first major singles title at the US Open in 1999.

• She was 17 years old at the time of that victory (specifically 17 years and 350 days).

So, to directly answer the question “at what age did Serena Williams win her first U.S. Open?”: she was 17 years old.

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