As of the time of the announcement, the season was in production and the showrunners stated that it will focus on a smaller group of core characters. Later, Brandon Vietti revealed that they will be doubling down on the core season one characters that fans already know and love.
On September 5, Greg Weisman said on DC Daily that season four would have 26 episodes, and that there would also be another time jump.
By October 2019, voice recording was already underway and storyboarding commenced two months later.
On September 12 2020, Weisman stated in a Q&A session during DC FanDome that their team has been working from home on season four. Pre-production was still underway despite the COVID-19 pandemic, but voice recording was being done individually by voice actors rather than in group sessions.
By November 23, all 26 scripts were finished and 22 episodes were fully recorded.