You will not normally have to pay tax on money whilst it remains in your pension pot.
There are three occasions which may result in you paying tax on the savings within your pension pot.
If you die before the age of 75, any money left in your pension pot can be usually be paid to your beneficiaries free of tax. If you die after the age of 75, any money that is left in your pension pot will usually be taxable when paid to your beneficiaries.
Depending on your financial circumstances and the option you choose, you may pay tax on the money you take from your pot. The money you take from your pot will be added to any other income you have for that tax year including State pension payments, benefits, salary etc. This may mean you pay a higher rate of tax in the tax year you take the money out. The tax year runs from 6 April one year to 5 April the next.
If you take the money in a number of different tax years you may pay less tax than if you take it all in one go.
You can speak to Pension Wise, HMRC or a financial adviser to further understand how your income option decision will determine the amount of tax you will pay.