I understand the rationale of total income exceed £100,000 then need to submit self assessment as the personal tax allowance will be reduced. But I am confused about Q4 in the tool which define pension contribution should be counted as income as well --> the 2nd bullet in Q4 stated "salary before tax and pension contributions" https://www.gov.uk/check-if-you-need-tax-return/ Assume a person just start working in 2022/23 and have unused pension contribution allowance £30,000 for 2022/23 If 2023/24 salary income for that person is $45,000 and his/her employer directly contribute £70,000 to SIPP in gross. As 2023/24 pension allowance is £60,000 so £10,000 should be automatically allocated to 2022/23 unused pension contribution allowance. In this case, by Q4 definition the total income for 2023/24 should be £45,000 + £60,000 = £105,000 and a self assessment is needed ?