Updated 30/09/2026

How to estimate the rent of a flat: a step-by-step method and rents in Czech regional capitals

Where to find a realistic rent for a buy-to-let flat, why asking prices in listings overstate it, how flat size changes rent per m² and rents in all Czech regional capitals (Deloitte Rent Index Q2 2026).

Rent is the most important number in the whole calculation. You know the purchase price exactly and the bank writes the interest rate into the contract, but the rent is only an estimate. And any error in it repeats 12 times a year for as long as you hold the flat.

What a 10 % error in rent costs

Take the default flat: 45 m² in Brno for 6.25 million CZK with a mortgage covering 80 % of the price. At a rent of 17,600 CZK (the Brno average according to Deloitte), the after-tax IRR comes out at 7.6 % and the calculator shows amber. If the flat actually lets for only 15,800 CZK, i.e. 10 % less:

the monthly top-up in the first year rises by roughly 1,500 CZK, and over 10 years you pay in about 230,000 CZK more,
the IRR drops from 7.6 % to 6.7 %,
in the pessimistic scenario the return falls below zero and the traffic light switches from amber to red.

And ten percent is a perfectly ordinary gap between what a listing asks and what the flat actually lets for.

The method in six steps

1. City average × floor area

Start with the average rent per m² in the city and multiply it by the floor area of the flat. The best regular source is the Deloitte Rent Index (quarterly, all regional capitals). The second source is the Ministry of Finance rent price map (cenová mapa nájemného): it is published quarterly within 45 days of the end of each quarter, distinguishes 4 size categories (1+kk and 1+1, 2+kk, 3+kk, 4+ and larger; "kk" means a kitchenette in the living room) and goes down to neighbourhood level. Both are based on asking prices from listing portals. The Ministry itself states that the map serves public administration and is not a tool for determining market rent. It is a starting point, not the answer.

2. Adjust for size

Smaller flats command noticeably higher rent per m². In Prague in 2025, rent for flats under 44 m² was around 491 CZK/m², while flats over 63 m² went for around 342 CZK/m², roughly 30 % less. Large flats also take longer to let. The city average therefore underestimates the rent of a studio and overestimates that of a 3+kk.

3. Find 10-15 comparable listings

On Sreality and Bezrealitky, filter for the same layout within roughly 1 km. Look for a similar floor, condition, furnishing and a balcony. Fewer than 10 listings is too few; a single expensive flat can easily skew the average. Work with the median, not the mean.

4. Take 5-10 % off the asking price

Listings show what landlords want, not what they get. In Prague, achieved rents have stagnated around 420 CZK/m² while asking rents kept rising. The portal average is also pushed up by expensive flats that stay on the market longest precisely because they do not let.

5. Check how long flats stay listed

In July 2026 the average rental listing stayed on the market for 23 days (CEMAP data). If comparable flats in your area sit there for two months, the asking price is above the market. On Sreality you can tell a listing's age from the date it was posted, or you can track the same flats for a few weeks.

6. Watch the season

In student cities the third quarter is markedly more expensive. In Q3 2025, rents for 3+kk flats rose quarter on quarter by as much as 18 % in Brno and 25 % in Olomouc. If you let the flat in September you will achieve a higher price, but do not treat it as the year-round average. In Prague the seasonal swing is small.

Rents in regional capitals (Q2 2026)

Asking rents according to the Deloitte Rent Index and an indicative rent for a 45 m² flat (excluding service charge advances, rounded to hundreds).

City	CZK/m² per month	45 m² flat (CZK/month)
Prague	462	20,800
Brno	390	17,600
Hradec Králové	318	14,300
Pardubice	314	14,100
Pilsen	301	13,500
Olomouc	296	13,300
Liberec	289	13,000
Zlín	287	12,900
České Budějovice	283	12,700
Jihlava	257	11,600
Ostrava	254	11,400
Karlovy Vary	246	11,100
Ústí nad Labem	221	9,900

The national average is 343 CZK/m². Differences within a city tend to be larger than those between cities: Prague 1 and Prague 14 differ more than Pilsen and Liberec.

What pushes rent up

A balcony or terrace, a parking space, good-quality furnishing, a new build with low energy advances and good public transport access. Nobody, however, publishes reliable percentages for how much each feature adds. So do not trust tables along the lines of "balcony + 10 %"; compare actual listings with and without a balcony instead. Note: the Ministry of Finance map assumes a reference flat without a balcony, terrace or garage.

The most common mistakes

Taking the rent from the seller or the agent. The current tenant may be paying below or above the market, and the lease may end soon.
Counting rent including service charge advances. Listings often quote "rent + fees" as a single figure, but the advances are not your income.
Applying the city average to a flat that is much smaller or larger than average.
Comparing with listings that have been up for months. Those are exactly the ones that did not let at that price.
Treating the September price in a student city as the year-round standard.

How the calculator estimates rent

If you do not enter a rent, the calculator takes the Deloitte Rent Index average for the chosen city and multiplies it by the floor area. The result will carry an estimate label. It is a sensible start but no substitute for steps 2-5: once you have your own estimate from comparable listings, overwrite it. Rent in the calculator is excluding service charge advances. With a long-term let the tenant pays these on top, and the owner covers them only in months when the flat is empty. To be safe, use What if… to see what a 10 % lower rent does.

Sources

This text is indicative and does not replace tax, legal or financial advice. For binding decisions consult a Czech tax adviser. · Privacy policy · Terms of use ·