At least 58, including English speaking countries like the U.S. which have no official language, but which are predominantly English: Antigua and Barbuda Australia Bahamas Barbados Beliza Botswana...
The following island countries* have English, either as their official language or as one of their official languages: Australia Bahrain Barbados Cuba Cyprus Dominica Grenada Iceland Jamaica Kiribati...
I was looking through the list and surprisingly, the US doesn't have English or any other language for that matter as an official language. Here's the list of countries that do in alphabetical order:...