Private Pensions

On the Self Assessment return it requests that you input your total gross pension income (I receive 4 pensions). I did that and at the final calculation it gave a figure of tax that I owe, my question is - what about all the Tax I paid before receiving the pension payments - surely that needs deducting from my balancing payment quoted? I did attempt to detail tax paid in the "any other information" box but it is a very sensitive tool..it rejects nearly everything I write in it.

Hi,
The box immediately after the box you completed should read 'Tax taken off pensions (other than state pensions), retirement annuities and taxable lump sums treated as pensions (optional)'. Enter the tax paid on your private pensions in this box.
Thank you.

I didn't do this..I am assuming I now need to update my existing return ?

Hi
Please refer to amending a return If you need to change your return