Canada (B) (NB) (P), China (mainland), Greenland (B) (NB), Iceland (B) (NB), Japan, Mexico, North Korea, Russia (Asian), South Korea, St Pierre and Miquelon (NB) (P), USA (B).
Vagrant to Austria, Belgium, Croatia (Local Name: Hrvatska), Denmark, France, Germany, Italy, Kazakhstan, Mongolia, Montenegro, Netherlands Antilles, Norway, Poland, Serbia, Slovakia (Slovak Republic) (NB), Svalbard and Jan Mayen Islands, Sweden, Switzerland, Ukraine, United Kingdom.
From L Baikal, Siberia, eastwards to Aleutian Is and Alaska, southwards to Colorado, USA. eastern Canada, Greenland and Iceland.
 
Population
Estimated population is 190,000 - 380,000 (2010).
Harlequin Duck (Histrionicus histrionicus) [XC351801]
by Stanislas Wroza from Washington (near Anacortes), Skagit County, Washington, United States (call)
Harlequin Duck (Histrionicus histrionicus) [XC209346]
by Stanislas Wroza from Moorecroft Regional Park, Nanoose Bay, British Columbia, Canada (call)