The short answer to this is ‘As soon as you can afford to’ but realistically this is likely to depend on at what age you started saving and how much of your earnings you save over your lifetime.
The amount of income your pension savings can generate depends on a number of factors.
One of the most important is your age when you buy an annuity: other things being equal, your annuity will generate much more cash every year if you buy it at age 70 than at age 60.
You will be able to buy an annuity at an age determined by the terms of your pension scheme – but no sooner than age 55, according to the law.
Pension options have really changed in the last few years - current legislation means you no longer have to buy an annuity with your retirement pot, so it's worth looking into what your options are.
The other major consideration when deciding to retire is when you are eligible for the state pension. This is currently at 65 for men and is also rising to 65 for women by 2018.
However, the government plans to raise this further to 66 for both sexes by 2020.
Because of these changes, different ages of people will see this increase happen at different speeds and calculating what your state pension age will be is complicated.
For this reason the government offers a free calculator.
Another thing to be aware of when choosing when to retire is that employers can no longer force you to retire at 65 unless they can clearly justify it.
Lastly, some, mostly public sector, professions allow for earlier retirement than others.
These professions will almost all have their own special pension arrangements taking this into account, which they will have made their staff aware of.