Heat the water in a small saucepan over medium-low heat until hot, but not boiling. Add the tea, remove from the heat and allow to steep for 4 minutes.
Place a fine mesh strainer over a bowl, then pour in the tea to catch the tea-infused water. If using tea bags, you can just remove them.
Return the tea-infused water to the saucepan, add the sugar, stir well, bring to the boil, then reduce the heat and simmer for 10 minutes.
Remove from the heat and allow the tea simple syrup to cool to room temperature. Carefully pour it into a sealable jar (a funnel helps) and store for up to 1 month in the fridge.