California ties the payment deadline directly to the notice you give. Under Labor Code §202, an employee who gives at least seventy two hours of notice must be paid all final wages on the last day worked, while an employee who quits without that notice is paid within seventy two hours. Late payment triggers waiting time penalties under Labor Code §203, a full day of wages for every day the check is late, capped at thirty days. Accrued vacation is vested wages under Labor Code §227.3, so use it or lose it policies are void. The notice date in your California letter is what starts the seventy two hour clock in your favor.
New York is flatter. Final wages are due on the next regularly scheduled payday under Labor Law §191, whether the separation was voluntary or not. Accrued vacation is different: under Labor Law §198-c, an employer may lawfully refuse to pay out unused vacation if it has a written policy saying so and the employee was notified of it. Read the handbook before choosing a last day, because timing a departure just past an accrual date can be worth real money.
Texas follows the Texas Payday Law at Labor Code §61.014, under which an employee who quits is paid on the next regularly scheduled payday, against six calendar days for a discharged employee. No vacation payout is required unless a written policy or agreement provides one, so the policy document is the whole story. Non-compete clauses are enforceable in Texas when reasonably limited, which makes the letter a poor place to name your next employer.
Illinois requires final compensation at the time of separation where possible, and no later than the next regularly scheduled payday, under the Illinois Wage Payment and Collection Act at 820 ILCS 115/5. Earned vacation must be paid out, and the state enforces that actively.
Massachusetts distinguishes sharply between quitting and being fired. Under Mass. Gen. Laws ch. 149 §148, an employee who resigns is paid on the next regular payday, while a discharged employee is paid the same day. Accrued vacation counts as wages, and the statute carries mandatory treble damages, which makes the state unforgiving of a payroll error on a departing employee.