I'm learning just how careful you have to be!
The only sugar free syrups at Starbucks are Vanilla and Cinnamon Dolce. I sometimes get a sugar free Cinnamon Dolce latte with fat free milk, but there are calories from the fat free milk but no calories from the sugar free syrup.
I like the unsweetened iced green tea - Zero calories, but you can add your own sugar free sweetner if you want. I keep liquid sugar free Stevia in my purse to use for hot or iced tea. Liquid Stevia is my sweetner of choice.
Just FYI.
Penny