Yes, "different than" is an Americanism. I believe that "different from" is most common across all dialects of English: http://alt-usage-english.org/excerpts/f

Yes, "different than" is an Americanism. I believe that "different from" is most common across all dialects of English: http://alt-usage-english.org/excerpts/fxdiffer.html http://alt-usage-english.org/excerpts/fxdiffer.html (Note: This only compares UK English and American English, not "all dialects".)