WPA is a three-letter abbreviation with multiple meanings:

• Walter Payton Award, awarded annually since 1987 to the best offensive player in Division I-AA football
• War Powers Act, also known as the "Trading with the Enemy Act" and commonly confused with the "War Powers Resolution", an American law aimed at domestic collaboration with the enemy during World War I
• Wi-Fi Protected Access, a wireless encryption standard and successor of Wired Equivalent Privacy (WEP)
• Windows Product Activation, a controversial licensing strategy introduced by Microsoft to curb unauthorized distribution of Windows XP.
• Woomera Prohibited Area, a former testing range for rockets, planes and nuclear devices
• Works Progress Administration (later "Works Projects Administration"), a New Deal government agency that provided jobs to unemployed people from 1935 to 1943 to mitigate the effects of the Great Depression
• Working People's Alliance, Guyanese political party
• World Pool-Billiard Association, the international governing body of pocket-billiard sports.
• World Poker Association, the international governing body of tournament poker worldwide.
• Win Probability Added, a technical baseball statistic.
• Western Provident Association, United Kingdom based Health Insurer

WPA