Vistra, a leading Fortune 275 integrated retail electricity and power generation company, is offering employees a chance to win a $50,000 cash prize for providing proof of being fully vaccinated.

The sweepstakes was launched in August, an added incentive after Vistra started awarding vaccinated employees $100 gift cards earlier this year.

Eight lucky employees will win a cash prize, ranging between $25,000 to $50,000; the size of the prize depends on how high the company’s total vaccination rate goes and will be awarded just before the holidays, allowing time for more employees to get vaccinated.