If you pay PRSI at the full rate (Class A) you will be eligible to receive social welfare benefits and pensions.  Because of this, the occupational pension that you will receive is co-ordinated with social welfare Contributory State Pension.   Employees who pay PRSI at Class D, pay a reduced contribution rate which means that they will not be eligible to receive social welfare benefits and pensions.  The occupational pension that they will receive is not co-ordinated with social welfare Contributory State Pension.