While philodendrons tolerate being root bound a little better than most houseplants, they don't actually like being root bound. Your plant will be happiest and healthiest if you do repot regularly. Get tips for repotting your houseplants.
Do I need to repot my philodendron?
Philodendron is a tropical plant that grows vigorously and requires frequent repotting if grown in a container. It actually responds very well to slight crowding, however, so with each repotting you should move it to a container that is only a little bit larger.
How do I know if my philodendron is root bound?
The roots stop growing actively, and as a result, the upper portions of the plant begin to show common pot-bound symptoms, such as frequent wilting, stunted growth, smaller new leaves, poor quality flowers or lack of flowers and yellowing and dropping older leaves.