The Library will be closed for the Thanksgiving Holiday on

Thursday, November 26 and Friday, November 27. 


The Library will be open on Saturday, November 28. 


We wish you and yours a Happy Thanksgiving!!


Welcome to the Mountainside Public Library

The Mountainside Public Library is located on Constitution Plaza in Mountainside, New Jersey. The library features a large selection of books, periodicals, movies, music, audiobooks and reference resources. There are also public computer workstations, free wireless Internet access, a community meeting room, a children's center and regularly scheduled entertainment and educational events.

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Library Hours

Monday: 10am to 9pm

Tuesday: 10am to 9pm

Wednesday: 10am to 5pm

Thursday: 10am to 9pm

Friday: 10am to 5pm

*Saturday: 10am to 5pm

Sunday: Closed

*Closed Saturdays from

July through Labor Day

Holiday Closings 2015
January 1: New Years Day

January 2: Day after New Year's
January 19: MLK Birthday
February 16: Presidents' Day
April 3: Good Friday
May 25: Memorial Day
July 3: Independence Day Observed
September 7: Labor Day
October 12: Columbus Day
November 11: Veterans' Day
November 26: Thanksgiving Day
November 27: Day after Thanksgiving
December 24: Christmas Eve: Close at 1pm
December 25: Christmas Day
December 26: Day after Christmas
December 31: New Years Eve: Close at 1 pm

Mountainside Public Library
1 Constitution Plaza
Mountainside, NJ  07092






Help the Friends of the Library support our programs and services by using Amazon Smile when you shop this holiday season.  

Upcoming Events


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The Mountainside Public Library is the proud first recipient of the
LUCCy Award!

The Libraries of Union County Consortium (LUCC) awards the LUCCy yearly to a Public Library in Union County to honor Excellence in Library Service.  Read more...