This image compares the income after tax for someone with taxable income of £125,000 before and after paying a personal pension contribution of £25,000 gross.
Before the contribution:
Taxable income £125,000
Personal allowance zero
Employee National Insurance £6,464.16
Empoyer National Insureance £16,058.78
Tax £42,500
Net pension contribution zero
Income after tax £76,035.84
After the contribution:
Taxable income £125,000
Personal allowance £12,500
Employee National Insurance £6,464.16
Empoyer National Insureance £16,058.78
Tax £32,500
Net pension contribution £20,000
Income after tax £66,035.84