The former McLaren driver was drafted in by the Anglo-French team as a late replacement for the cash-strapped Pastor Maldonado, and went on to secure seven of the team's eight points during the 2016 campaign.
He will move to Haas next season after being replaced by Nico Hulkenberg, and ended up retiring from his final Grand Prix with Renault last Sunday after contact with Daniil Kvyat.
"It wasn't the way I wanted to end what I thought was a good season with a great bunch of people," he said. "Results-wise it hasn't been the best but I've learned a lot, I've had a great time with the team."
Despite reports of conflicts with team management, Magnussen wished the team well for the future.
"I wish Renault all the best in the future and I'm sure we'll all still have fun in the paddock," he said.
Next season will see Magnussen become the first driver to sample an engine from each of the current four engine manufacturers, having driven with Mercedes and Honda power at McLaren, driving for Renault this year, and Ferrari-powered Haas next year.
Bahrain International Circuit - Winter testing