Start by working out what income you need in retirement in today's money. There are tables that suggest what you need for a frugal life style, a comfortable lifestyle and well off lifestyle.
Let's say you want £35k a year (hopefully any kids will have left home, you'll be mortgage free, no commuting costs etc)
Subtract the state pension amt of £12500 which you'll get at 67.
That means you need £22500 from a private pension.
A pension pot invested on the stock market will give you around 4.7% return annually.
£22500÷0.047 = £478,723
So you need to have £479k in a pension to give you an income of £22500 pa.
If you have equity in a property and you can downsize when you retire, you should include the equity left after buying a smaller house in your pension pot (you would put it in an ISA then any growth and interest and dividends are tax free)
You really need to be saving hard to invest the amount of money you need to deliver this.
Make sure you are getting full tax benefits from your pension contributions. If you run your own ltd company then the company should contribute before corporation tax is paid and there's no limit to how much can be put in by your company.
Then check what your pension is invested on. You need low cost funds with a good geographic and market spread. With a minimum of 12 years to grow you should be looking at high risk investment. For example a ftse100 or ftse250 index tracker, a European market tracker, a US index tracker, and a rest of world tracker. Reinveat all dividends (called accumulation funds, not income funds). With growth and dividend payouts with a lot of saving you could do it
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