For covered, nonexempt employees, the Fair Labor Standards Act (FLSA) requires overtime pay (PDF) to be at least one and one-half times an employee's regular rate of pay after 40 hours of work in a workweek. Some exceptions apply under special circumstances to police and firefighters and to employees of hospitals and nursing homes.
Texas has special exemption laws regarding overtime.
Extra pay for working weekends or nights is a matter of agreement between the employer and the employee (or the employee's representative).
The Contract Work Hours and Safety Standards Act (CWHSSA) requires contractors and subcontractors on most federal contracts over $100,000 for services or construction to pay laborers and mechanics at least one and one-half times their basic rate of pay for all hours worked over 40 in a workweek. CWHSSA also applies to most federally assisted construction contracts.
Learn more about overtime on the US Department of Labor's website.