Timblin is a borough in Jefferson County, Pennsylvania, United States.

[3] The community which would later be named as "Timblin" had its genesis in the arrival, during the early 1800s, of several pioneer settlers in Perry Township: James McClelland (1803), Benjamin Ions (1804), David Hamilton (1806).

[7] The town grew quickly, following the 1910 completion nearby of an extension of the Pittsburg, Shawmut & Northern Railroad.

[9] The First National Bank of Timblin was incorporated in July 1918 and opened its doors to customers on October 22 of that year.

A special election was held for Timblin residents on January 30, 1923, during which T. L. Miller was chosen as the borough's burgess, John Milliron was elected as constable, Charles Snyder was chosen as assessor, Wayne Anderson and E. O. Weaver were elected as Justices of the Peace, David Haas was chosen as tax collector, and Amos Brosius, Harry Brosious, A. J.

In addition, S. B. Engle, D. C. Griffith, James R. Marshall, G. H. Maxwell, Duff W. McGregor, J. C. Milliron, and Dr. L. W. Zimmerman were elected to the borough council, and N. L. Boddorf, V. G. Brosius, and J.

According to the United States Census Bureau, the borough has a total area of 0.95 square miles (2.47 km2), of which 1.7 acres (7,036 m2), or 0.28%, are water.

Timblin is in the valley of Pine Run,[15] a west-flowing tributary of Mahoning Creek, part of the Allegheny River watershed.