I am UK based and I had got a good bonus in April 2021 which tipped me over 100k, for example, let's say that's an annual incoming of 125k between April 2021 and April 2022 including the good bonus.
HMRC had adjusted my tax code starting August 2021 and each month, I have got extra tax £700-£800ish deducted but I didn't understand why back then.
Only recently I have figured out that's because my personal allowance goes down by £1 for every £2 above the income limit of £100k. And because of that, I have lost £12k of my personal allowance.
If I didn't contribute to any pension during this period, before the end of this fiscal year (e.g. 05/04/2022), is it still possible to get the lost £12k personal allowance back? If so how ? and would add some of my savings into a SIPP help on that at all? If so how much do I need to add to it? and how can I claim the lost £12k back?
The company I work for won't allow me to do Salary Sacrifice at this stage until the window opens for the next financial year in April.