We often get asked this question by investors who are scratching their heads as they can't see the relevant box to carry back the SEIS income tax relief on their personal tax return.
Here is a quick video tutorial showing you exactly how to claim income tax relief related to the previous tax year:
So the key is to dig out your Form SEIS3 (you will need it in any case to properly file your claim for SEIS tax relief, regardless of whether you are intending to carry the relief back).
Fill out page 3 and send it to your tax office. This effectively amends your prior year submitted tax return.
This can be a useful tool for tax planning, if for example, you have insufficient income tax suffered in the most recent tax year to be able to absorb all 50% SEIS tax relief on your investment.