In general, they mean the same. But many writers prefer to use "due to" because it is shorter than "because of". In headline writing, shorter is better.

Both sound okay and are used frequently in spoken english, but grammatically, there is a big difference. Without going into the nuances, here is a simple technique to know what is right : Replace "Due to" with "Caused by". If it sounds right, then "due to" has been used correctly. e.g. Calf Dairies going broke caused by Feed, milk prices -> WRONG ! hence Due to cannot be used here. CORRECT : Calf Dairies going broke because of Feed, Milk prices Due to rising feed, milk prices, calf dairies are going broke Read the detailed explanation here : http://www.dailywritingtips.com/because-of-and-due-to/ http://www2.elc.polyu.edu.hk/cill/exercises/because.htm P.S. : This is only for people who are really strict about grammar. Otherwise the tone of the sentence is not affected by either of these and you can use any without any problem in spoken language :)

If you were writing an article, I would stick with "due to" because it sounds a little more formal and "intellectual". If you are speaking, "because of" would sound more natural.