In Jainism there is no universal scriptural ban on tea. However:

• Most Jains avoid tea (and coffee) because they are stimulant beverages and can affect purity of mind and self-control, which are important in practicing ahimsa and gupti (mindful living).
• The stance tends to be stricter among some followers and more lenient among others, especially depending on whether one follows a Digambar or Śvetambar household tradition.
• The common practical guidance from many Jain teachers is to prefer simple, plain, non-stimulating drinks to keep the focus on non-violence and mental clarity.

If you want, I can look for a specific Jain source or a teaching from Digambar vs. Śvetambar traditions to quote more precisely.