Many states offer vacation payout at termination, although these payout are typically contingent on other criteria, e.g., time of employment, etc. In other states, the vacation payout at termination by state protocols put the option of vacation payouts in the hands of employers. What does your state say about vacation payouts after you get your final check?
While it is common for many states and employers to offer vacation payouts at the end of an employee's tenure with an organization, there are often stipulations and guidelines that dictate when, how much and so on. It is always advisable to check with your employer to understand the terms of your employment contract.