BA or Ba may stand for:
- ba
- an archaic two-letter English word meaning "to kiss".
- in Egyptian mythology:
- One part of the Egyptian soul (which was imagined as a bird body with a human head).
- A ram-god of fertility, worshipped especially in Mendes. Women desiring a pregnancy prayed to him for help.
- Bachelor of Arts, see Bachelor's degree
- barium (Ba) , the chemical symbol for the chemical element
- Boeing Company (stock symbol)
- Bosnia and Herzegovina (ISO country code)
- British Airways