The short answer is "yes" ... if the subordinate clause comes at the beginning of the sentence.
A subordinate clause adds context to a sentence. It is not a proper sentence on its own.
A subordinate clause starts with a subordinate conjunction. Common subordinate conjunctions are: after, although, as, because, before, even if, even though, if, in order that, once, provided that, rather than, since, so that, than, that, though, unless, until, when, whenever, where, whereas, wherever, whether, while, and why. In the following sentences, we have put the subordinate clauses in bold.
Lisa chose to visit the High Court since she's a law major.
Since Lisa is a law major, she chose to visit the High Court.
If you go to the conservatorium, you will learn something about music.
You will learn something about music if you go to the conservatorium.
From these examples, you can see that subordinate clauses can either come at the beginning or end of a sentence. When subordinate clauses come at the end of the sentence, you don't use a comma. However, when a subordinate clause comes at the beginning of the sentence, you set it off with a comma.