Both “due to” and “owing to” can be used to mean “because of”. Many people use the two words interchangeably.
Here are a few examples. *Owing to/Due to bad weather, all flights were cancelled. *Ramesh was late, owing to/due to the heavy traffic. *Owing to/Due to the groom’s illness, the wedding was postponed. *The wedding was postponed due to/owing to the groom’s illness.
Careful users of the language argue that “due to” should not be used at the beginning of a clause. But even educated native speakers of English begin clauses with “due to”.
One difference between “due to” and “owing to” is that “due to” can be used after the verb “to be”; “owing to”, on the other hand, cannot.
For example, it is OK to say, “Their success was due to hard work and brilliant planning.” You cannot say, “Their success was owing to hard work.” Similarly it is OK to say, “The actor’s success was due to his wife”, but you cannot say, “The actor’s success was owing to his wife.”