Steaming cup of tea on table
The Best And Worst Type Of Tea For Increasing Hydration

When it comes to hydrating your body, tea is a great alternative to water because it is almost entirely made of water, with the exception of any added sugar or fruit.

However, caffeinated teas can actually dehydrate you, as caffeine is a diuretic, and a lot of the liquid you are consuming just flows through you.
Sugar is also an enemy of hydration and can have a diuretic effect, so something like a Southern-style sweet black tea, which is high in sugar and caffeine, is your worst bet.
Black tea, green tea, and matcha have the highest caffeine levels, but white tea and oolong tea have caffeine, too, so try replacing them with decaf and cut down on added sugar.
As for caffeine-free alternatives, you can buy pre-packaged herbal tea blends. You can also steep ingredients with your tea in hot water, strain, and drink hot or chilled.
These include berries, citrus and tropical fruits, ginger root, basil, mint, and rosemary. Fresh or dried lavender, chamomile, rose, echinacea, hibiscus, and jasmine can work too.
Your spice cabinet is also full of potential. Aromatic spices like cinnamon, bay leaves, cloves, and star anise can serve as excellent additions to your favorite caffeine-free tea.