The Black-chinned Hummingbird is known as the "kissing cousin" of the Ruby-throated. At 8-9 cm (3 in.) in length, it is the same size as its eastern counterpart and is very similar in appearance. Adult males have a black throat with deep purple iridescence on the lower half which is only visible in good light. As a result, it often appears that the entire head is black. Females and immature Black-chins are almost identical to their Ruby-throated cousins. This species has a longer, slightly downward curving bill. The back is not as bright green as the Ruby-throated. The tips of the outer primaries (wing feathers) are more rounded but this is difficult to see in flight. The Black-chinned Hummingbird has a habit of pumping its tail, while perched or flying. This is the best clue to identification.
There have been several reports to date of this species in Ontario, including one confirmed Black-chinned north of Lake Superior. These birds can be readily mistaken for Ruby-throats so it is possible that this species is underreported when visiting Ontario and other eastern provinces and states.