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Rental yield calculator

What goes in, what comes out each month, and what it returns. Fill it in by hand, paste a Sreality or Bezrealitky link, or open it from any flat for sale on Bytky: the asking price, the estimated rent and the usual Czech costs are filled in for you, and every figure can be changed.

Start from a listing

Paste a Sreality or Bezrealitky link to a flat for sale. Bytky fills in its asking price, estimated rent and costs.

An example to start from: a 50 m² flat for 6,000,000 Kč, let for 24,000 Kč a month. Replace the figures with yours, or fill them in from a listing above.

Purchase
Financing

Loan 4,200,000 Kč · Down payment 1,800,000 Kč

Same after the fixation

For a flat bought to let, ČNB recommends a loan of at most 70% of the value and a total debt of at most 7 times your net yearly income. These are recommendations to banks: shown as a hint here, never enforced. ČNB's limit for a mortgage on your own home is 80% of the value (90% if you are under 36).

Rent
Running costs

a month

a month

of the rent

of the rent

Income tax

Filled in with the average wage, so your basic credit of 30,840 Kč a year is already used. With no other income, that credit usually covers the tax on one flat's rent.

of the price

Simplified estimate, not tax advice. It uses 2026 rules for every year.

How long you hold it

Cash flow after tax−1,736 Kč a month

Gross yield4.8%

What it returns

Costs you 1,736 Kč a month at 24,000 Kč rent; break-even rent 25,881 Kč.

Cash flow after tax
−1,736 Kča month
Before tax: −1,736 Kč a month
Gross yield
4.8%
Net yield
4.1%
Cash-on-cash return
−1.2%
Break-even rent
25,881 Kč
Debt service coverage
0.92×
Mortgage payment
22,393 Kč
Cash needed up front
1,817,000 Kč

Income tax: 0 Kč a year. Over 10 years, the “Actual expenses” method costs 279,000 Kč less tax than the other one.

Year by year

Cash flow, loan, equity and return for each year held
YearRentRunning costsMortgageTaxCash flowCumulativeLoan leftFlat's valueEquityTotal return
1265,846 Kč17,961 Kč268,716 Kč0 Kč−20,831 Kč−20,831 Kč4,137,359 Kč6,000,000 Kč1,862,641 Kč24,810 Kč
2265,846 Kč17,961 Kč268,716 Kč0 Kč−20,831 Kč−41,662 Kč4,071,551 Kč6,000,000 Kč1,928,449 Kč69,787 Kč
3265,846 Kč17,961 Kč268,716 Kč0 Kč−20,831 Kč−62,493 Kč4,002,418 Kč6,000,000 Kč1,997,582 Kč118,089 Kč
4265,846 Kč17,961 Kč268,716 Kč0 Kč−20,831 Kč−83,324 Kč3,929,793 Kč6,000,000 Kč2,070,207 Kč169,883 Kč
5265,846 Kč17,961 Kč268,716 Kč0 Kč−20,831 Kč−104,155 Kč3,853,498 Kč6,000,000 Kč2,146,502 Kč225,347 Kč
6265,846 Kč17,961 Kč268,716 Kč0 Kč−20,831 Kč−124,986 Kč3,773,348 Kč6,000,000 Kč2,226,652 Kč284,666 Kč
7265,846 Kč17,961 Kč268,716 Kč0 Kč−20,831 Kč−145,817 Kč3,689,145 Kč6,000,000 Kč2,310,855 Kč348,038 Kč
8265,846 Kč17,961 Kč268,716 Kč0 Kč−20,831 Kč−166,648 Kč3,600,689 Kč6,000,000 Kč2,399,311 Kč415,663 Kč
9265,846 Kč17,961 Kč268,716 Kč0 Kč−20,831 Kč−187,479 Kč3,507,762 Kč6,000,000 Kč2,492,238 Kč487,759 Kč
10265,846 Kč17,961 Kč268,716 Kč0 Kč−20,831 Kč−208,310 Kč3,410,141 Kč6,000,000 Kč2,589,859 Kč564,549 Kč

Cash flow is after tax. Equity is the flat's value less the loan left. Total return is the equity plus the cash flow so far, less the cash put in; it assumes no sale, so no selling costs or tax on a sale.

Your scenarios

Save the figures to come back to them, compare up to three side by side, or share a read-only link.

How it is worked out

Everything is computed in your browser, in whole crowns, with the same code that produces the yield card's figures. Nothing you type is sent anywhere unless you save a scenario.

The maths

  • The mortgage is a monthly annuity: equal instalments of principal and interest, the interest each month a twelfth of the yearly rate on what is left. The instalment is rounded to a crown and worked out again when a fixation ends on a different rate. Banks round differently, so theirs may differ by a few crowns.
  • Rent received is twelve months of rent for the weeks the flat is let, grown once a year by the rent growth you set. Running costs stay flat in today's crowns.
  • Cash flow is the rent less running costs, the upkeep reserve and the agent's fee, less the year's mortgage payments, less the income tax on the rent. Repaying the loan is cash out even though it builds equity, so equity is shown separately.
  • The tax is the extra income tax the rent causes: the tax on your other income plus the rent's profit, less the tax on your other income alone. The profit is the rent less actual expenses (running costs, mortgage interest, depreciation) or the flat-rate share. A loss is carried forward for five years. Letting your own flat under §9 carries no social or health insurance. It assumes your other income is about the average wage, so the basic credit is already used; set 0 if the rent is your only income.
  • Gross yield is a year of rent over the price. Net yield is the first year's income after running costs over the price, purchase costs and renovation. Cash-on-cash is the first year's cash flow, before tax, over the cash you put in.

What is left out

  • Selling the flat: its costs, and any tax on the gain.
  • Costs rising with inflation; they stay at today's amounts.
  • Letting for only part of the first year, or buying and letting in different years.
  • Tax credits and deductions other than the basic credit, and a loss from letting set against other income.
  • Bank fees, valuations, insurance of the loan and early repayment.
  • When repair-fund payments become deductible: they are treated as deductible when paid, which some advisers dispute.

Every default, and where it comes from

Each figure the calculator starts with is a named constant with its source and the day it was checked. Verified ones were read from the law or the official statistic; assumptions are typical values you should replace with your own.

FAQ

Frequent questions

More about Bytky as a whole, from what it costs to where the data comes from.

Read the main FAQ

What is a good rental yield in the Czech Republic?

On the asking prices and rents Bytky tracks, the median gross yield of a flat for sale was about 3.2% in Prague, 3.5% in Brno and 4.0% in the rest of the country on 13 October 2026. Higher yields are found outside the big cities, and usually come with a smaller market and more risk. A yield is only half of it: what it returns after the mortgage and tax is the cash flow this calculator works out.

What is the difference between gross and net yield?

Gross yield is a year of rent divided by the price. Net yield first takes off the weeks the flat is empty and the running costs (repair fund, administration, insurance, property tax, and anything you set aside for upkeep), and adds the purchase costs and any renovation to the price. Neither includes income tax or the mortgage.

How is the mortgage payment calculated?

As an annuity: equal monthly instalments over the term, at a monthly rate of a twelfth of the yearly rate. When the fixation ends the instalment is worked out again for what is left, at the new rate. Your bank's offer will differ by a few crowns and by its own rate.

How is rental income taxed in Czechia?

Letting your own flat is §9 income under the Income Tax Act. The profit is added to your other income and taxed at 15% up to 1,762,812 Kč a year (36 times the average wage) and 23% above it, after a basic credit of 30,840 Kč. No social or health insurance is due on it. This calculator charges the rent what it adds to your tax and says so: it is a simplified estimate, not tax advice. It assumes your other income is about the average wage, so the basic credit is already used; set it to 0 if the rent is your only income.

Should I deduct actual expenses or use the 30 % flat rate?

With the flat rate you deduct 30% of the rent (up to 600,000 Kč a year) and nothing else. With actual expenses you deduct running costs, mortgage interest and depreciation, which wins when they come to more than that, as they often do with a mortgage. The calculator shows both and which costs less tax over your horizon. The choice is made for the whole year and can't be undone afterwards.

What does the calculator leave out?

The sale of the flat (its costs and any tax on the gain), costs rising with inflation, bank fees, tax credits other than the basic one, and letting for part of a year. The methodology above lists them.

Is this financial advice?

No. It is a simplified estimate built on asking rents and prices to help you think. Ask a tax adviser and your bank before you decide.

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