Question: is rsi number the same as pps number

Answer: No, The PPSN was known as the Revenue and Social Insurance Number (RSI No) until 1998. RSI Numbers were first issued in April 1979 as a replacement for the separate PAYE Number and Social Welfare Insurance Number which had been used for income tax and social welfare purposes respectively until then. The PAYE Number was issued by the Revenue Commissioners and these numbers were transferred to the RSI No system as a basis for the unified system.