Images of the indexes to the New York City Clerk’s collection of marriage affidavits, licenses, and certificates may now be accessed for free through the Internet Archive at https://archive.org/details/nycmarriageindex&tab=collection . These indexes were formerly available on microfilm only at the New York City Municipal Archives.
Instructions for how to obtain copies by mail of the actual records appears on the description page of every volume.
So far 48 volumes have been posted for:
Manhattan 1908-1929
Brooklyn 1908-1929
Bronx 1914-1917
Additional images will soon be uploaded for:
Bronx 1918-1929
Queens 1908-1930
Staten Island 1908-1938
For the years 1908 to 1937, New York City kept two sets of marriage records. Most, but not all, couples reported their marriages to both the City Clerk and the New York City Department of Health. See Leslie Corn’s article, “City Clerk’s Marriage Licenses, New York City, 1908–1937: One of 20th Century Genealogy’s Best Primary Sources.” NYG&B Newsletter (now New York Researcher), Spring 1999. Members can view an updated version (2003) published in the New York Knowledge Base.