In Disney World, the latest layoffs will affect only part-time employees after union negotiations.
Universal says it now expects the economic impact of the COVID-19 pandemic to stretch into 2021.
"SeaWorld has determined that it must transition certain park and corporate personnel from a furloughed status to a permanent layoff," the company said in a statement.
The agreement includes mandatory face masks for guests and employees and paid sick leave for any worker who contracts COVID-19.
Amid the coronavirus pandemic, Disney World is furlough 43,000 unionized employees starting April 19. Their health benefits are guaranteed for the next year.
The temporary layoffs will apply to executive, salaried, and non-union hourly employees at Disney World as well as Disneyland.
J.P. Morgan has suggested Disney furlough some theme park employees in April to save money during the coronavirus pandemic.