Williams has announced that it will continue with Mercedes power until at least 2025.
The team’s current deal was set to expire at the end of 2020, marking the new contract a five year extension on the existing agreement.
“We have enjoyed a wonderful partnership with Mercedes-Benz over the past six years of what was originally a seven-year agreement, and so we are delighted to be continuing working with them for a further five years from 2021,” said deputy team principal Claire Williams.
“Mercedes-Benz has been one of the sport’s most successful engine suppliers and we believe that they will continue to have an extremely competitive engine package going forwards.
“Over our time with them they have become a real friend of the team, and we look forward to working with Mercedes-AMG HPP in future.”
Toto Wolff, who heads Mercedes’ motorsport programs, added: “Williams is one of the iconic brands in Formula One and we at Mercedes are proud to count them as part of our motorsport family.
“They have been through some tough times recently but that has only served to demonstrate their resilience and strength of character as they battle back to where they belong on the grid.
“I am certain that the outlook for independent teams is bright under the financial regulations that will be introduced from 2021 and we are delighted to continue our partnership with Williams into that new era of our sport.”
Running its own factory effort, Mercedes has been the standout performer in the current hybrid engine formula.
Introduced in 2014, the Anglo-German marque, whose engines are developed in Brixworth in the UK, have claimed both drivers’ and constructors’ titles in each subsequent season.
Under the current engine regulations, the Mercedes engines proved the dominant power unit, though more recently the likes of Ferrari, Renault, and Honda have all made strong progress to peg back that advantage.
However, though it supplies engines to Racing Point and Williams alongside its factory effort, none of its customer teams have won a race with Mercedes power.
Mercedes has supplied customer engines to Williams since 2014, which initially saw the team’s flagging fortunes reversed.
Williams finished third in the 2014 constructors’ championship behind Mercedes and Red Bull, a marked improvement over the ninth place finish with Renault engines the previous year.
In more recent years it’s again slowly slipped down the totem pole, and in 2018 finished last with just seven points to its name.
The team’s last win came courtesy of Pastor Maldonado at the 2012 Spanish Grand Prix.