Contrary to popular belief, starting a sentence with “because” is not necessarily a grammatical error. This rule can also apply to the word "since."

Using “because” at the beginning of a sentence is grammatically correct when it is used as a subordinating conjunction. This is sometimes called a “dependent word” or “subordinator.” A subordinating conjunction is a word that allows for an inversion in the normal sentence structure; it allows a dependent clause to come first. A comma is used to connect the dependent and independent clauses. It all works out like so:

Correct: Because I lack creativity, this example sentence is not fun.

Using “because” at the beginning of a sentence is not grammatically correct when the clause is made to stand on its own. When "because" is used as a subordinating conjunction, it causes the clause it is in to become a dependent clause and thus a sentence fragment. For the sentence to be completed, it requires the addition of an independent clause. Here’s how it doesn’t work out:

Incorrect: Because television stole my soul.

So now you know that using “because” at the beginning of a sentence can in fact be used correctly, does this mean you use this form at every opportunity? The answer to that is no. Just because it is grammatically correct, that does not mean that it is good form for all occasions. In more formal writing, you may want to shy away from using “because” at the beginning of a sentence. This is similar to avoiding passive voice in formal writing.

Disclaimer: I may have stumbled upon this one grammar rule, but I am in no way a grammar fiend. Please /msg about any grammar errors in this write-up that would make me look silly in an ironic sort of way. Please ignore any possible incorrect usage of the word irony. Thank you