Rent, costs, Section 24 and the SA105 boxes
Every rent payment, cost and mortgage interest payment for up to 20 properties, with your share worked out if you own jointly, and your tax for the 2026/27 tax year. Excel and Google Sheets.
What you get
- Excel workbook, 11 tabs and 7 chartsStart here, Settings, Dashboard, Properties, Rent log, Expenses, Mortgage and interest, Certificates and dates, Yield calculator, Property tax calculator, SA105 box map
- Google Sheets versionA make-a-copy link puts it in your own Drive in one click
- 11 page PDF guideMortgage interest and Section 24, the tax calculator with a worked example, payments on account, the box map and safety dates
- Open me first pageThe Google Sheets button and the three things to do first
Why this one
- Section 24, worked outResidential mortgage interest is no longer a cost. The calculator takes 20% of the lowest of the three figures HMRC names and carries any unused part forward.
- SA105 boxes from the current formBox 20, boxes 24 to 29, box 36 and boxes 38 to 45, so you copy each figure straight onto your return.
- A UK safety calendarGas safety every year, the electrical check every five years and the EPC every ten, with Overdue and Due within 60 days coloured for you.
- Joint owners and commercial unitsType the whole amount, set your share once, and every figure becomes your share. Interest on a shop or unit goes to box 26 as a cost.
- Ready for the new property ratesProperty income gets its own rates from April 2027, 22%, 42% and 47%, and the calculator shows your year at those rates beside this one.
How it works
- Set up and add your propertiesOn Settings, where you live for tax and your salary or pension. On Properties, each property with your share
- Log the moneyEach rent payment, cost and interest payment, for the whole property. Pick a category and the SA105 box fills in
- Copy the boxesRead your tax on Property tax calculator and copy each box from SA105 box map
Who it is for
UK landlords with one to twenty properties who do their own Self Assessment: accidental landlords, couples who own a flat together, and anyone with a buy-to-let beside a job. SA105 is the UK property pages of your tax return. Section 24 is the rule that stops you taking residential mortgage interest off your rent as a cost and gives you a 20% tax credit instead. Not for property held in a limited company.
Questions
Do I need Microsoft Excel?
No. It comes with a Google Sheets version, which is free with a Google account. The Excel file also opens in the free web version of Excel.
How do I get it?
Straight after payment it is in your library on this site: the Excel file, the PDF guide and the Open me first page with the Google Sheets button.
I own a property with my partner. Does it work?
Yes. Type each payment for the whole property, set your share once on Properties, and every figure on the tax calculator and the box map becomes your share.
I hold my properties in a limited company. Is it for me?
No. It is built for landlords who own property in their own name and file Self Assessment, not for property held in a company.
Is this tax advice?
No. Every figure is an estimate to help you prepare your return. Check your figures, or ask an accountant, before you file. Every rate sits in its own cell with its source, so you can update it when HMRC changes it.
Made by Izhar Shah. I built a brand in the evenings alongside a full-time engineering job, and in its first twelve months it passed £500,000 in sales. I make the sheets I wish I had when I started.
Works in
Instant access in your library after payment. Every figure is an estimate to help you prepare your return, not tax advice.