Pruitt will now earn $4.2 million per year, though he's elected not to accept his 2020 raise to help the Volunteers' athletic department combat challenges faced during the COVID-19 pandemic, Low adds.
The 46-year-old originally signed a six-year, $22.8 million deal in December 2017, meaning he's now signed through 2025.
The two sides began discussing a new pact in January, but talks were put on hold when the pandemic hit.
Pruitt is entering his third season as Tennessee's head coach. After going 5-7 in his first campaign, the Volunteers finished third in the SEC East in 2019 with an 8-5 record (5-3 in conference play).
Tennessee, currently No. 16 in the AP Poll, kicks off its upcoming season Saturday against South Carolina.