SA105 Form: How to Complete Your Property Tax Return

The SA105 is the supplementary page you attach to your self-assessment tax return to report UK property income. If you earn any rental income, you need to fill this in. It’s not complicated, but getting the numbers wrong can trigger an HMRC enquiry.

How to Fill In the SA105

You’ll report total rental income, then deduct allowable expenses line by line. The form covers property income, expenses, private use adjustments, and losses brought forward. Our landlord tax deductions guide lists every expense you can claim so you don’t leave money on the table.

Making Tax Digital and the SA105

Making Tax Digital for landlords is changing how you report property income. Instead of one annual return, you’ll submit quarterly updates. But the SA105 categories stay the same — income, expenses, profit. Start categorising your records now and the transition will be painless.

Common SA105 Mistakes to Avoid

Forgetting to claim the mortgage interest tax credit. Mixing up repairs and improvements. Not carrying forward losses from previous years. Use the buy-to-let tax calculator to cross-check your numbers before submitting, and read our complete landlord guide for the full picture of your obligations.

Full guide coming soon.