Is tea a countable or uncountable noun?

The noun 'tea' is an uncountablenoun as a Word for a substance. Units of tea are expressed as a pot of tea, a cup of tea, a package of tea, etc.

The plural form 'teas' is reserved for 'types of' or 'kinds of'; for example:

The teas on the menu are green tea, jasmine tea, and lemon grass tea.