How much to save
Key dates
Profit build-up
Add income from a client
Income this year
| Date | Client | Description | Status | Amount | GBP | Fee |
|---|
Add a business expense
Expenses this year
| Date | Description | Category | Allowable | Amount |
|---|
Home working allowance
Choose how to claim the cost of working from home. The app uses whichever you select as an allowable expense.
Simplified flat rate
Calculated allowance
Personal pension contributions
Personal pension contributions get basic-rate (20%) relief added to your pot automatically. If your profits reach the 40% or 45% band you claim the extra relief through Self Assessment — this app works that out for you. Pension contributions reduce your Income Tax but not your National Insurance.
Net → gross is grossed up by ÷0.8 (adds 20%). Annual allowance is generally £60,000 (2026/27), and you can't get relief on contributions above your relevant earnings — this tool doesn't cap for that, so keep within your limits.
Your pension tax relief
Self Assessment estimate
Income Tax breakdown
National Insurance
Payments on account
Your profile
Saved to your account and used across every tax year. These details appear at the top of your CSV export.
Business & tax details
Defaults for new work
Your account
Tax rates for
These are pre-filled with the confirmed rates. Edit them to model changes or a future year, then Save. Reset restores the official figures.
Options
Data
All data is stored privately in this browser only. Nothing is uploaded. Back up regularly.