Use supplementary pages SA110 to record the results of your tax calculation on your SA100 Tax Return.
Use the SA110 supplementary pages when filing your SA100 Tax Return to record the amount due or overpaid for:
- Student Loan repayments
- Class 4 National Insurance contributions
You should include in the calculation any:
- underpaid tax
- payments on account
- surplus allowances
- adjustments to tax due
Only complete the SA110 supplementary pages if you’re calculating your tax liability.