2013 Citi Open – Women's singles

Magdaléna Rybáriková was the defending champion, and she successfully defended her title, defeating Andrea Petkovic in the final, 6–4, 7–6(7–2). This was Rybáriková's final WTA singles title before her retirement in 2020.

Seeds
• # 🇩🇪 Angelique Kerber (quarterfinals)

• # 🇺🇸 Sloane Stephens (first round)

• # 🇷🇺 Ekaterina Makarova (semifinals)

• # 🇫🇷 Alizé Cornet (semifinals)

• # 🇷🇴 Sorana Cîrstea (quarterfinals)

• # 🇩🇪 Mona Barthel (second round)

• # 🇸🇰 Magdaléna Rybáriková (champion)

• # 🇺🇸 Madison Keys (second round)

Seeds
• # Michelle Larcher de Brito (qualified)

• # 🇺🇸 Jessica Pegula (qualified)

• # 🇷🇺 Vera Dushevina (withdrew)

• # 🇺🇸 Irina Falconi (qualified)

• # 🇦🇷 María Irigoyen (first round)

• # 🇻🇪 Adriana Pérez (first round)

• # 🇯🇵 Shuko Aoyama (qualifying competition)

• # 🇺🇸 Victoria Duval (qualifying competition)

• # 🇺🇸 Ashley Weinhold (first round)

Qualifiers
• # Michelle Larcher de Brito

• # 🇺🇸 Jessica Pegula

• # 🇺🇸 Alexandra Mueller

• # 🇺🇸 Irina Falconi