Mortgage parameters
Move the sliders or type values directly. Result updates instantly.
Principal and interest month by month
At the start, interest takes up to 70% of your payment — the bank takes most of what you pay. This gradually flips: by the end, almost everything goes to principal.
| # | Period | Payment | Principal | Interest | Balance |
|---|
Already have a mortgage and looking for better?
Put two offers side by side and see which saves more.
How a Czech mortgage payment is calculated
When a Czech bank quotes you a 4 million CZK loan for 25 years at 4.43 %, it tells you the monthly payment is 22,075 Kč. Where does that number come from? In the Czech Republic, 99 % of mortgages are annuity-based — the monthly amount stays the same for the entire fixation, calculated from one formula. Here's the full breakdown.
The annuity formula
The monthly payment of an annuity mortgage is:
M = P × r × (1 + r)n / ((1 + r)n − 1)
Where: M = monthly payment, P = principal (loan amount in Kč), r = monthly rate (annual ÷ 12, as decimal), n = number of monthly payments (years × 12).
Step by step on a real example
Compute the monthly payment for a 4,000,000 Kč mortgage at 4.43 % p.a. for 25 years:
- Monthly rate: r = 4.43 ÷ 100 ÷ 12 = 0.003692
- Number of payments: n = 25 × 12 = 300
- (1 + r)n = (1.003692)300 ≈ 3.02185
- M = 4,000,000 × 0.003692 × 3.02185 / (3.02185 − 1) = 22,075 Kč
Headline rate vs. RPSN — what you actually pay
When comparing offers from Czech banks you'll see two percentages:
- Nominal interest rate — what banks advertise (e.g. "4.43 %"). This drives the annuity formula above.
- RPSN (annual percentage rate of cost) — total annual cost including processing fees, account fees, mandatory insurance. Always higher than the nominal rate.
Always compare offers by RPSN, not the headline rate.
Czech mortgages in 2026 — context
The ČNB holds its 2T repo rate at 3.50 %, and the average new mortgage rate per the ČBA Hypomonitor is around 4.43 %. Specific bank offers run 4.2–4.8 % depending on profile, LTV, and fixation. For a quick run on your own numbers use the mortgage calculator on hypoteky.com — free, no sign-up.
Frequently asked questions
How exactly is the monthly mortgage payment calculated?
Using the annuity formula: M = P × r × (1 + r)n / ((1 + r)n − 1), where P is the loan amount, r is the monthly rate (annual ÷ 12), and n is the number of months. Annuity means you pay the same amount every month — only the principal/interest split changes.
What is an annuity payment and why is it standard in CR?
An annuity payment is a fixed monthly amount throughout the fixation period — easy to budget, predictable. The alternative is "even principal" repayment (interest decreases, total payment shrinks), but it's not common for Czech mortgages. 99 % of Czech mortgages are annuities.
Why am I paying mostly interest in the early years?
Interest is calculated on the current outstanding balance. Early on the balance is high, so 60–70 % of each payment goes to interest. As the balance shrinks, interest in each payment shrinks too. Near the end almost the whole payment goes to principal.
What's the difference between rate and RPSN?
The nominal rate (e.g. 4.43 %) is what the bank uses in the annuity formula. RPSN (annual percentage rate) is the total annual cost including processing fees, servicing, mandatory insurance. RPSN is always higher than the nominal rate, typically by 0.2–0.5 %. Always compare banks by RPSN.
Which loan term should I choose?
Longer term (30 years) = lower monthly payment, dramatically more total interest. Shorter (15–20 years) = higher monthly payment, hundreds of thousands saved. A practical compromise: take the maximum term and use extra payments to shorten it actively.
What happens to my payment after fixation ends?
The bank recalculates the payment using the current market rate. The annuity formula stays the same, but with a new r and n (remaining months). If your old rate was much lower than market, the new payment will be substantially higher. Use the calculator's "+1 %" / "+2 %" scenario toggle to see the impact.