How to Value a Property for Buy-to-Let
A property is only worth what it earns. Yield, not asking price, decides whether a buy-to-let works. Here is the maths every landlord should run before they offer.
On this page+
# How to Value a Property for Buy-to-Let
A buy-to-let is a small business, not a house. The price you pay is justified only by the income it produces and the risks attached. This guide shows the maths to run before you sign on the dotted line.
Step 1: Establish achievable rent
Do not trust the estate agent. Cross-check:
- Rightmove sold prices for the same street and similar properties.
- OpenRent and SpareRoom for current asking rents.
- Zoopla rental estimates by postcode.
- Local letting agents — ask 2 to value as if you were instructing them.
- HomeLet rental index for regional averages.
Take the median of your sources. Discount 5% for safety.
Step 2: Calculate gross yield
Gross yield = (annual rent ÷ purchase price) × 100
Example:
- Purchase price: £200,000
- Achievable rent: £1,200/month = £14,400/year
- Gross yield = (14,400 / 200,000) × 100 = 7.2%
Benchmark by region:
| Region | Typical gross yield range |
|---|---|
| North East | 7–10% |
| North West | 6–9% |
| Yorkshire | 6–9% |
| Midlands | 5–8% |
| East / South East | 4–6% |
| London | 3–5% |
| Norfolk / Norwich | 5–7% |
HMOs typically yield 2–4 percentage points higher than single lets, but with higher costs and admin.
Step 3: Calculate true purchase cost
Most landlords budget the asking price and forget the rest.
| Item | Typical cost |
|---|---|
| Stamp Duty + 3% surcharge | 3–8% of price |
| Legal fees | £1,200–£2,000 |
| Survey | £400–£800 |
| Mortgage arrangement fee | 1–2% of loan |
| Mortgage broker fee | £0–£995 |
| First-year insurance | £250–£600 |
| Initial refurb / decoration | £2,000–£15,000 |
| Furniture (if furnished) | £3,000–£8,000 |
| Voids / first-month carrying cost | 1 month rent |
| Contingency (10%) | varies |
For a £200,000 property add roughly £20,000–£30,000 to get true entry cost.
Step 4: Calculate annual running costs
| Cost | Typical |
|---|---|
| Mortgage interest | 4–6% of loan balance |
| Landlord insurance | £250–£600 |
| Letting agent (if used) | 8–12% of rent (full management) |
| Maintenance budget | 1% of property value |
| Voids | 4% of rent (≈ 2 weeks/year) |
| Gas safety, EPC, EICR, PAT | £200–£400 |
| Licensing | £100/year amortised |
| Accountancy | £200–£500 |
| Membership/software | £100–£300 |
For the £200,000 / £14,400 example with a 75% LTV mortgage at 5.5%:
- Mortgage interest: £8,250
- Maintenance: £2,000
- Voids: £600
- Compliance: £300
- Insurance: £400
- Accountancy: £300
- Letting agent (self-managed): £0
Total costs: £11,850. Net income: £14,400 - £11,850 = £2,550.
Step 5: Calculate net yield and ROI
Net yield = (net income ÷ purchase price) × 100 = (2,550 / 200,000) × 100 = 1.275%
That looks small — but you only invested cash (deposit + entry costs), not the full price.
Cash invested = £50,000 deposit + £25,000 entry costs = £75,000 ROI = (2,550 / 75,000) × 100 = 3.4%
Plus capital growth (if any) on the full £200,000 value, plus mortgage principal repayment over time.
Step 6: Stress test
Run the numbers again with:
- Interest rate +1% (so 6.5% instead of 5.5%).
- Voids at 8% instead of 4%.
- Maintenance at 2% instead of 1%.
If the deal still breaks even, it is a buy. If it goes negative, you are betting on capital growth alone — which is speculation, not investment.
Step 7: Check the lender's view
Buy-to-let lenders use the Interest Coverage Ratio (ICR):
Rent must cover 125% (basic-rate taxpayer) or 145% (higher-rate) of mortgage interest at a stressed rate of 5.5–7%.
Example: £150,000 loan at 7% stress = £10,500/year interest. At 145%, you need £15,225/year rent (£1,269/month). If your achievable rent is below this, the lender will not lend the full 75%.
Red flags that kill deals
- Service charges or ground rents above £500/year — eats yield.
- Cladding or EWS1 issues — currently un-mortgageable for many flats.
- Short lease (<85 years) — extension cost reduces yield.
- Spray foam insulation in loft — lender refusal common.
- Japanese knotweed within 7m — survey downvalue.
- Subsidence history — premium loaded for years.
- HMO in selective area without licence in place.
- EPC F or G — un-lettable from April 2025 unless exempt.
What a "buy" looks like
For a beginner self-managing landlord in 2026:
- Gross yield: 7%+
- Stress test passes at 7% interest.
- True entry cost ≤ 115% of asking price.
- ROI 5%+ before capital growth.
- EPC C or better.
- No service charge / freehold preferred.
- Local rental demand evidenced by 3+ months SpareRoom data.
Common mistakes
- Buying the property you would live in, not the one that pays.
- Ignoring service charges on flats.
- Forgetting Section 24 — higher-rate taxpayer mortgage interest is only 20% relievable in personal name.
- Not budgeting voids and maintenance.
- Buying on capital growth alone.
Use the Smart Sleep Property buy-to-let yield calculator in the Landlord Tools centre to run any property in 30 seconds.
Frequently asked questions
What is a good gross yield in 2026?+
6%+ for single lets, 8%+ for HMOs. The further south you are, the harder these are to find.
What is the difference between gross and net yield?+
Gross yield uses annual rent vs purchase price. Net yield deducts mortgage interest, maintenance, voids, insurance and compliance costs first.
How do I value a property the lender will agree with?+
Use comparable sold prices from Land Registry and Rightmove for the same postcode and property type in the last 6 months. Lenders use the same data.
What stress test do BTL lenders apply?+
Rent must cover 125% (basic rate) or 145% (higher rate) of the mortgage interest at a notional 5.5–7% rate, depending on lender and product.
Should I buy on capital growth or yield?+
Yield is contractual; growth is speculation. Buy on yield and treat growth as a bonus. If a deal only works on assumed growth, it does not work.
How much should I budget for refurbishment?+
£10–£25 per square foot for cosmetic refresh, £50+ for a kitchen/bathroom replacement, £100+ for full strip-out. Always add 15% contingency.
Does location matter more than yield?+
Both matter. A 10% yield in a falling area can still be a poor investment. Look at population trends, employment, transport and crime data.
Are flats or houses better for BTL?+
Houses usually have higher yields, no service charges, more control. Flats are cheaper to enter and easier to let in urban centres but service charges erode yield.
How do I check rental demand?+
Search Rightmove and SpareRoom for the postcode — number of listings vs days on market. Speak to 2 local letting agents and ask about tenant waiting lists.
What is the impact of Section 24?+
Higher-rate landlords in personal names cannot deduct mortgage interest from rental profit — only a 20% tax credit. Limited company structures avoid this.
Should I use cash or mortgage?+
Mortgaged deals usually deliver higher ROI on cash invested, but lower net yield. Cash deals are more resilient to interest rate changes.
How accurate are online valuation tools?+
Within 10% for typical 3-bed semis in average areas. Less reliable for HMOs, unusual properties, or rapidly changing markets.
Get the tools to handle this confidently
Our Membership gives self-managing landlords across the UK Renters' Rights Act–compliant tenancy templates, compliance reminders, document storage and member pricing on services — from just £9/month.