The 457(b) is a supplemental retirement plan that allows employees to set aside payroll-deducted contributions on a pre or after-tax basis. NC 457 Plan Highlights.A 457(b) plan is a tax-deferred retirement savings plan. Funds are withdrawn from an employee's income without being taxed and are only taxed upon withdrawal. The plan must be limited to provide benefits for a select group of management or highly compensated employees. Of 2008, amounts paid as differential military pay are included in the Code definition of includible compensation. Deferred compensation allows individuals to set aside income to be paid at a later date, offering potential tax advantages and retirement savings opportunities. The Transfer Benefit provides a monthly stream of income for life which meets an IRS requirement for an exception to the penalty.