As usual with pensions, it is more complicated than it should be.
For Personal Pension Plans, it's sometime between 60 and 75. You do not have to retire from work to receive the benefits.
For PRSAs, it is possible to take the benefits from 50 onwords, but in this case you must retire from work. Otherwise, anytime between 60 and 75.
There are different rules concerning retirement due to ill-health or for certain occupations where early retirement is the norm ie sportsmen