としても is used to say that even if a certain condition is true, the outcome or statement in the main clause remains unchanged. It often implies that the speaker thinks the condition might happen but wants to emphasize that it doesn't affect their decision or opinion. It is more formal than ても but still common in everyday speech, especially in written or reasoned contexts.

Unlike ても, which simply states a contrast, としても sets up a stronger hypothetical: it frames the condition as something you are 'assuming' or 'granting' for the sake of argument. For example, saying 行くとしても means 'even assuming I go', which often carries a nuance of 'but that doesn't mean I'll stay long'. You can also use it with a past form like 行ったとしても to emphasize the completed action, meaning 'even if it happened'.

In conversation, you often hear it in polite refusals or conditions: 買うとしても、高すぎる means 'even if I were to buy it, it's too expensive'. Note that when the subject is different from the main clause, you must use だ (e.g., 休みだとしても).