Once the beta is enabled for your firm, every individual client gains a Self Assessment entry in their menu. Open the client from your Individuals list and choose it — Tax Optimiser creates the 2025-26 return automatically the first time, so you land straight in the capture screen.
Personal details come pre-filled
The Personal Details section is snapshotted from the client’s record when the year is created: name, National Insurance number and address are already in place, and stay with the return even if the client record changes later. Set the Taxpayer status here — Rest of UK, Scotland or Wales — because it drives which Income Tax bands the calculation uses.
The blue header shows the tax year, the client’s name and their UTR, so you can always see whose return is open. Two things worth checking before you go further:
- The client’s Unique Taxpayer Reference must be on their Tax Optimiser record (open Individual from the menu to add it). It has to be the real ten-digit UTR: the pre-flight checks test it against HMRC’s check-digit rule and will not let a return without a valid one reach HMRC.
- The National Insurance number in Personal Details is required for filing too.
Pick the pages the return needs
A Self Assessment return is the core SA100 plus whichever supplementary pages apply. Press Add Section and tick the pages this client needs — each one appears in the left-hand menu. The pages are grouped under Income, Other supplementary pages and Reliefs and repayments, and each tile carries a line saying what belongs on it, so it is easy to tell the short self-employment page from the full one.
Tick exactly what this client’s return needs; anything left unticked stays out of the menu and the filing. Unticking a section later just hides it: the data is kept, so nothing is lost if you change your mind, and a tile whose page already holds entries is marked Has figures so you can see what you would be hiding.
Finding your way around
The left-hand menu lists the sections in the order of the return. A green dot beside a section means figures have been entered on it, and a red number beside Calculation counts the problems that would stop the return being filed online. Click any section to open it, or use Back and Next at the foot of the screen to work through the return in order — the footer also shows which section you are on and whether your changes are saved.
Everything saves as you go
Each box saves when you leave the field, and the tax calculation re-runs automatically. The card at the top of the section menu updates within a moment of each entry: it shows the Total Tax Due by 31 January, including any first payment on account, or Repayment Due when the client has overpaid. There is no separate save button to remember — the footer reads All changes saved once an entry is stored. If you type something into a money box that is not a number, the box turns red, says it has not been saved, and keeps what you typed so you can correct it.
Next: Entering income.
