Do I have to contribute the same amount to every employee’s HSA?

Generally, employer contributions must be comparable, that is they must be in the same dollar amount or same percentage of the employee’s deductible for all employees in the same “class”. However, with the passage of a new law in 2007, higher 
contributions are allowed for non-highly compensated employees. In addition, you can vary the level of contributions for full-time vs. part-time employees, and employees with self-only coverage vs. family coverage. You do not need to consider employees who have not elected the high-deductible health plan coverage because they are not eligible for HSA contributions.