LANDLORD MONEY · GUIDES & TOOLS
Sources and tax assumptions
Inspect official sources, effective dates and verification dates.
THE DETAIL BEHIND THE NUMBERS
What this means for your calculation
The calculator uses versioned rule data linked to HMRC and GOV.UK. Verification means the source figures were checked on the date shown; it does not certify an individual's tax result. Unsupported facts are not filled in using older rules.
In practice
The 2026/27 individual tax period and the Corporation Tax financial year have different start and end dates. Both are shown in the source register.
How can I report a discrepancy?
Use the contact page once operator contact details are configured. Include the tax year, source link and a non-identifying example; do not send addresses or tax identifiers.
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
Information, not advice. Landlord Money provides estimates for general information and educational purposes only. It does not provide tax, accounting, financial, investment, mortgage or legal advice. Tax treatment depends on individual circumstances and may change. Check calculations with HMRC and consider professional advice before making financial, ownership or tax decisions.