Monthly cashflow
Calculating…Once let, after allowances and mortgage payments
THE BTL REALITY DEAL DESK
Buy-to-let
deal analyser.
See the deal behind the asking price. Know your cash in, your cashflow and what it could take to get your money back out.
Your numbers.
The whole picture.
YOUR DEAL, AT A GLANCE
THE DEAL SNAPSHOT
Does the deal
stack up?
Cash required
…Deposit + refurb + purchase costs + initial holding costs
Gross yield
…Annual headline rent ÷ purchase price
ROCE
…Annual cashflow ÷ initial cash invested
Equity created
…Valuation gain after acquisition, refurb and holding expenses
Free PDF download + email copy.
01 / CASHFLOW
Where the rent goes.
Your cash in
Your equity position
02 / PRESSURE TEST
Room for the unexpected.
RATES +2 PERCENTAGE POINTS
Your monthly cashflow
Same term, rent and running costs.
| Rate | Payment / mo | Cashflow / mo | Cashflow / yr |
|---|
| Change | Rent / mo | Cashflow / mo | Cashflow / yr |
|---|
03 / LOOK AHEAD
Explore your route to money all out
The five- and ten-year picture.
04 / CAPITAL RECOVERY
When could you get
your money back out?
A projection, not a promise. Compare keeping rental profits with releasing equity through a possible refinance.
When cumulative cashflow covers your original cash investment. No sale or extra borrowing.
Profit + potential releaseRental cashflow savedInitial cash invested
See the full year-by-year projection
| Year | Property value | Mortgage balance | Equity | Monthly cashflow | Cashflow saved | Potential release | Cash still invested |
|---|
The projection assumes you retain all rental cashflow. Losses reduce the cumulative total. A refinance release is extra borrowing, not profit, and is tested separately at each date. The indicative loan is capped by LTV and rental coverage. Full affordability, valuation and lender criteria are not assessed. No sale is assumed.
UNDERSTAND THE DEAL
A good yield is
only the start.
Two properties with the same rent and price can leave very different amounts in your pocket. The deposit, mortgage, refurbishment, purchase costs and ongoing allowances all change the picture.
This buy-to-let calculator puts the main numbers together. Use it to compare scenarios, challenge an asking price and prepare better questions for your broker and other advisers.
The example is a set of editable assumptions. It is not a recommended deal, a valuation or a prediction of future returns.
Cashflow
Rent after a voids allowance, management, maintenance, other monthly costs and mortgage payments. Results are before tax.
Yield & ROCE
Gross yield compares headline annual rent with purchase price. ROCE here means annualised rental cashflow divided by your initial cash invested. It excludes capital growth.
Equity created
Estimated post-refurb value less the purchase price, refurb, purchase and initial holding expenses, excluding principal repayments. Total property equity is shown separately as value less mortgage debt.
HOW THE PROJECTION WORKS
The assumptions stay visible.
The initial market value grows at your selected rate, compounded monthly. Any extra refurb value is added when the initial holding period ends and grows from that date. Rents and other fixed monthly costs increase after each complete year. Percentage allowances move with rent. The mortgage rate stays constant. Repayment loans amortise monthly and stop charging payments once repaid. Interest-only debt stays outstanding; the projection assumes it can continue on equivalent terms without a balloon payment or renewal fees.
Initial holding cash covers mortgage payments and fixed running costs before letting. Principal repayment is a transfer into equity, not an expense. No rent is earned during those months. The main cashflow and ROCE figures show a stabilised, fully let operating year with the voids allowance applied.
What “money all out” means here
At each eligible month, potential net release equals your refinance loan-to-value multiplied by the projected value, capped by rental coverage, minus the outstanding loan and refinance costs, subject to the minimum net release you set. We add cumulative rental cashflow once and compare that with your initial cash invested.
The model tests one refinance at a time. The post-refinance cashflow shown uses the new loan and your refinance rate. Repayment mortgages include capital repayments. Income tax, selling costs, irregular major repairs and changes in lending criteria are not modelled. Use your own figures and professional advice before committing.
FROM DEAL MATHS TO A REAL PLAN
The numbers are step one.
Know your next move.
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Deal analysis,
explained.
Does this include stamp duty and purchase taxes?
Yes. Automatic mode estimates ordinary resident additional-property SDLT in England and Northern Ireland, LBTT plus ADS in Scotland, or higher-rate LTT in Wales. Tax depends on the transaction and buyer. Special corporate rules, non-resident surcharges, reliefs, lease rent or mixed-use cases need a checked manual amount. Rates were checked on 26 September 2026.
What is the difference between yield and return on cash?
Gross yield is annual headline rent divided by the agreed price. Net operating yield includes operating costs and uses the price, refurb, buying costs and initial holding expenses as its denominator. Return on cash compares annual rental cashflow after mortgage payments with the initial cash required. All are before income tax.
Does equity release count as profit?
No. A refinance releases borrowed cash and increases debt. The calculator tests one possible refinance at each date, after fees, subject to your LTV and rental coverage assumptions. It never adds releases from different dates together.
Can I model a repayment mortgage?
Yes. Select Capital repayment in Finance. The model splits interest and principal every month and reduces the mortgage balance. Monthly cashflow deducts the full payment, while equity benefits from the debt reduction. Interest-only loans retain their balance.
How do I enter the purchase discount?
Enter the agreed price, then either your estimated market value or discount percentage. The two stay linked. Paying £180,000 for a property you estimate is worth £200,000 is a 10% discount. This is your assumption, not an independent valuation.
How is equity created calculated?
It is the estimated post-refurb value less price, refurbishment, acquisition costs and holding expenses. Mortgage principal paid during the holding period remains your equity rather than an expense. Total equity is a separate figure: estimated value less debt.
What does the full report include?
Your optional PDF includes the complete purchase and finance breakdown, operating costs, cashflow, returns, rate and rent stress tests, five- and ten-year milestones, annual projections and every assumption. Enter your name and email to download it and receive a copy. Your on-screen result needs no sign-up.
BTL Reality · Educational deal analysis, not a valuation, mortgage offer or personal financial advice. Results are illustrative and rounded for display.
Further reading: MoneyHelper on buy-to-let mortgages and GOV.UK on rental income and tax. Read our disclaimer.