The main/obvious benefit is to provide for retirement income in addition to any other retirement income (e.g. state Old Age Contributory or Non Contributory Pension) that you might qualify for. There are also generous tax/PRSI reliefs on pension contributions and up to 25% of the pension fund value can be taken as a tax free lump sum at retirement if you choose. Somebody who does not already own their own home might want to prioritise that over starting a pension unless there are employer contributions on offer that they must match to benefit from.