Dunlop has agreed to extend its deal as official tyre supplier and title sponsor of the BTCC for a further five years until the end of 2021.
The British firm first became the championship's sole tyre supply from 2003, taking over from BF Goodrich, and concluded an agreement to become the naming rights sponsor to the BTCC from 2005.
As part of the new agreement, Dunlop's HiQ brand will also continue to sponsor the teams' championship.
"I'm genuinely delighted that the BTCC will maintain its incredibly successful relationship with Dunlop right through until the end of 2021," said BTCC series director Alan Gow.
"Ours is one of the closest and most enduring of any major motorsport programme, so for the BTCC to continue to use Dunlop's superb race tyres whilst also carrying the Dunlop name in our title is something of great pride to our championship."
Dunlop's Hans Vrijsen added: "Dunlop is a powerful brand with high performance drivers. Dunlop is also synonymous with top level motorsport, having won the Le Mans 24 Hours more than any other tyre company.
"The BTCC gives Dunlop an opportunity to demonstrate its performance credentials in front of hundreds of thousands of passionate BTCC fans every year. We are delighted to be continuing this strong partnership."