When you use because, you give a main clause after that: I eat an apple every day, because it is healthy. You can only use a noun after due to: Due to the high volume of responses, we are only able to contact successful candidates. The delay of the train was due to the strike. You can rewrite the second sentence in many other ways: The delay of the train was due to the strike. (subject + to be + due to + noun) The train was delayed because of the strike. (consequence + because of + noun) The train was delayed because the drivers are on strike. (consequence + because + main clause) Due to the fact that the drivers are on strike, my train was delayed. (due to the fact that + main clause + , + consequence) In general, due to is a little bit more formal. I hope it helps to understand.

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