In America some of the easiest and most common ants that are kept as pets are: black wood ants (Formica fusca), fire ants, red stinging ants, pavement ants (Tetramorium caespitum) and carpenter ants (Camponontus pennsylvanicus).
It is always best to keep ant species that are local to your area. Its worth finding out which common species are in your area if you are planning on going out to catch them. The best way to do this is to use our regional ant locator, browse to your country and search for common ant species. If this fails you can use the search bar at the top right of the screen i.e. searching ‘common ant species England‘. AntWeb.org is a great resource for printing identification images of ants when you are out in the field.