What does McLaren's future look like now Mercedes are staying in F1?

McLaren not a works team

With Mercedes confirming they'll be on the 2021 grid, this means the team will have to develop an entirely new chassis to fit the new regulations. As this is a sizeable investment, it's unlikely the Silver Arrows will just fold after the one year into the new era.

McLaren, who will be driving with Mercedes engines in the back of their cars for the first time in six years next season, will therefore not become Mercedes' works team again.

Up until the end of 2009, this is essentially what McLaren was, comparable to the relationship Red Bull Racing now have with Honda - the only customer. With Mercedes' announcement of staying on the grid, McLaren's wish of becoming a works team again will not come true.

Even if Mercedes leave...

Even if Mercedes decide to leave the grid after 2021, chances of McLaren being their new works team are very slim. They won't leave like Honda did in 2009, literally shutting down the whole operation at once (before Ross Brawn famously acquired it and won the title). Should Mercedes leave the sport, they will definitely remain an engine manufacturer.

Currently, Williams and Racing Point race with Mercedes power units, and Williams have a contract until 2025. Aston Martin have expressed interest in becoming a works team themselves when they take over from Racing Point, but it should be noted Mercedes have a minority stake in the British carmaker.

All of this means McLaren will not get preference over other teams, and definitely not over Mercedes' own team if they remain in the sport.

Same situation as 2014?

In 2014, Ron Dennis decided to part ways with Mercedes as engine partners as he knew McLaren would never be champions as a Mercedes customer as long as the Germans themselves had a works team. He chose Honda to provide the Woking-based team's cars instead, and the team might be faced with a similar dilemma in the future.