SA110
Tax Calculation
HMRC's mandatory tax calculation summary, built from everything reported on your SA100 and SA103.
What it's for
Pulls together your income, allowances, and any deductions already made (like CIS) to arrive at your final tax due or refund figure. This has to be present before HMRC will accept your Declaration.
Who uses it
Every Self Assessment submission — it's generated automatically for you, not something you fill in yourself.
Limits & things to know
This is generated automatically from your other answers — there's nothing for you to enter directly here. The figure shown on your Review step mirrors what gets submitted in this section.