Montclair (/mɒntˈklɛər/ or /mɒŋˈklɛər/) is a township in Essex County, New Jersey, United States. As of the 2010 United States Census, the township's population was 37,669, reflecting a decline of 1,308 (-3.4%) from the 38,977 counted in the 2000 Census, which had in turn increased by 1,248 (+3.3%) from the 37,729 counted in the 1990 Census. As of 2010^[update], it was the 60th-most-populous municipality in New Jersey.

Montclair was first formed as a township on April 15, 1868, from portions of Bloomfield Township, so that a second railroad could be built to Montclair. After a referendum held on February 21, 1894, Montclair was reincorporated as a town, effective February 24, 1894. It derives its name from the French mont clair, meaning "clear mountain" or "bright mountain."

In 1980, after multiple protests filed by Montclair officials regarding the inequities built into the federal revenue sharing system, Montclair passed a referendum changing its name to the "Township of Montclair," becoming the third of more than a dozen Essex County municipalities to reclassify themselves as townships to take advantage of federal revenue sharing policies that allocated townships a greater share of government aid to municipalities on a per capita basis.

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