LANDLORD MONEY · GUIDES & TOOLS
How the calculations work
Review the model, tax ordering, limitations and rounding.
THE DETAIL BEHIND THE NUMBERS
What this means for your calculation
Property cash flow is rent after voids, less running costs, finance costs, non-allowable cash costs and capital repayments. Personal tax is the difference between total liability with the portfolio and liability on other income alone. Salary and dividends are added sequentially so mixed portfolios share allowances and bands.
In practice
Calculations use decimal arithmetic without intermediate penny rounding. Displayed figures round to two decimals, midpoint away from zero. This is an annual estimate, not HMRC return-box rounding or a payroll run.
How are property-level taxes allocated?
The dashboard allocates aggregate personal tax in proportion to positive taxable property profit, and company taxes in proportion to positive company profit. These are presentation allocations, not standalone tax assessments.
Model boundaries
UK-resident individuals in England, Wales and Northern Ireland; ordinary UK residential lettings; a single UK property company; full-year category A directors. No savings income, tax credits, personal pension deductions, Gift Aid, marriage allowance, non-resident rules, trusts or mixed-use property. Existing other property profit is assumed already net of allowable costs with no additional finance relief.
Company accounting period
Company figures represent a financial-year 2026 accounting-period scenario wholly within 1 April 2026 to 31 March 2027. Short-period amounts must be entered as period totals expressed through annualised input fields. No apportionment across financial years or brought-forward company reserves/losses is modelled. Salary is assumed wholly and exclusively allowable. Current-year company losses receive no immediate relief in this model.
Tax allocation and cash flow
Personal rental tax is measured before company extraction. Incremental salary and dividend tax includes resulting changes to allowance, existing dividend tax and finance relief. Negative company cash means funding is required, not a personal receipt. Property allowances replace tax deductions but never remove actual cash expenses.
Configured 2026/27 rates
| Rule | Configured value |
|---|---|
| Standard Personal Allowance / taper starts | £12,570 / £100,000 |
| Non-savings rates (including personal property income) | 20% / 40% / 45% |
| Taxable basic / higher band upper limits | £37,700 / £125,140 |
| Dividend allowance / rates | £500 / 10.75% / 35.75% / 39.35% |
| Employee NI primary threshold / upper limit | £12,570 / £50,270 |
| Employee NI main / upper rates | 8% / 2% |
| Employer NI secondary threshold / rate | £5,000 / 15% |
| Employment Allowance (if eligible) | £10,500 |
| Property allowance / finance-cost reduction rate | £1,000 / 20% |
| Corporation Tax small / main rate | 19% / 25% |
| Company lower / upper profit thresholds (before adjustments) | £50,000 / £250,000 |
Verified source register
| Rule / official source | Effective period | Verified |
|---|---|---|
| HMRC — Income Tax, Class 1 NI and Employment Allowance | 06 Apr 2026 – 05 Apr 2027 | 28 Sept 2026 |
| HMRC — Personal Allowance taper | 06 Apr 2026 – 05 Apr 2027 | 28 Sept 2026 |
| HMRC — Dividend tax | 06 Apr 2026 – 05 Apr 2027 | 28 Sept 2026 |
| HMRC — Corporation Tax financial year 2026 | 01 Apr 2026 – 31 Mar 2027 | 28 Sept 2026 |
| HMRC — Marginal Relief | 01 Apr 2026 – 31 Mar 2027 | 28 Sept 2026 |
| HMRC — Property allowance | 06 Apr 2026 – 05 Apr 2027 | 28 Sept 2026 |
| HMRC — Residential finance costs | 06 Apr 2026 – 05 Apr 2027 | 28 Sept 2026 |
Tax rates last verified: 28 September 2026 · Official sources