Not sure how my comment got posted twice. Sorry about that. Anyway, both species are highly variable and can be confusing. The broad dark malar (side of the throat) stripe, gray and white supercilium (above the eye) stripe, and the fairly long tail are good marks for Song Sparrow. Savannah Sparrow generally has a smaller, pinkish bill, at least a little (sometimes a lot) of yellow in the supercilium, lighter, finer streaking, and a shorter, pointier tail.
