Buy-to-Let Calculator
Calculate rental yields, mortgage costs, and investment returns
Last updated: February 2026
Property Details
LTV: 75.0% (min 25% deposit for BTL)
Annual: £14,400
Mortgage
vs Repayment
Loan: £187,500
Expenses & Tax
Maintenance, insurance, management
Empty periods between tenants
For tax band calculation
Net Monthly Profit (After Tax)
-£123
Negative cash flow
Annual Profit
-£1,475
Negative Cash Flow
This property costs you £123/month to run. Consider increasing rent or reducing costs.
Income Breakdown
Expenses Breakdown
Purchase Costs
Key Metrics
Rental Coverage Ratio
140%
✗ Below 145% ICR requirement
Break-Even Rent
£1,231
Monthly rent to cover all costs
Below ICR Requirement
Most BTL lenders require rental income to be at least 145% of mortgage payment. You may struggle to get a mortgage at this rent level.
Understanding Buy-to-Let
⚠️ Major Tax Changes Since 2020
You can no longer deduct mortgage interest from rental income before calculating tax. Instead, you get a 20% tax credit on mortgage interest paid.
Before April 2020
Rental income: £15,000
Mortgage interest: -£8,000
Expenses: -£2,000
Taxable: £5,000
Tax (40%): £2,000
After April 2020
Rental income: £15,000
Expenses: -£2,000
Taxable: £13,000
Tax (40%): £5,200
Less 20% interest credit: -£1,600
Final tax: £3,600
Higher and additional rate taxpayers are hit hardest by these changes. This calculator includes Section 24 effects.
Typical Lender Criteria
- • Minimum 25% deposit (75% LTV max)
- • Interest Coverage Ratio: Rent must be 125-145% of mortgage payment
- • Minimum income: £25,000/year (some lenders)
- • Age limits: Usually under 75 at end of term
- • Minimum property value: £40,000-£50,000
- • Maximum number of BTL properties: Varies by lender
Interest-Only
- • Lower monthly payments
- • Better cash flow
- • No capital repayment
- • Most common for BTL
- • Need repayment strategy
Repayment
- • Higher monthly payments
- • Build equity over time
- • Own property at end
- • Worse cash flow initially
- • Lower LTV over time
Tax year 2026/27 | Stamp Duty includes 5% BTL surcharge (raised from 3% in Oct 2024) | Tax includes Section 24 mortgage interest restrictions
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