DSTI and DTI

What does each abbreviation measure?

Both answer the same question from a different angle: can you carry the repayment?

DSTI looks at the month. It adds up the repayments on all your loans, including credit cards and leasing, and compares them with your net monthly income. It measures what's left once you've paid.

DTI looks at the whole picture. It compares your total debt with your net annual income, giving a multiple. It measures how big a burden you're taking on relative to what you earn.

Why aren't these CNB limits?

Because the regulator has switched them off for loans on your own home, and confirmed this again in June 2025.

LTV, the share of the loan against the value of the mortgaged property, remains binding. That is the only across-the-board indicator banks must keep to today.

You will still find, on dozens of websites, the line that "the CNB allows a repayment of at most half of income". That's outdated wording, copied from one article to the next. What this means for you in practice: if one bank says no because of your repayment-to-income ratio, that isn't a rule set by the state, it's a decision by that bank. Another bank may see it differently.

Where does DTI still apply?

For properties bought to let. Since April 2026 the Czech National Bank has recommended that, for these, total debt should not exceed seven times net annual income, together with a stricter LTV.

It is a recommendation, not a legal limit. But banks follow it, so in practice you will run into it. We cover this on the refinancing page too, since it also applies to transferring an existing loan onto an investment property.

How do banks calculate it now?

Each in its own way, and none of them publish it.

Banks keep an eye on both indicators as part of their own lending policy and factor them into price: a better repayment-to-income ratio usually means a better band, and with it a better rate. Nobody will tell you in advance how much, because internal pricing by creditworthiness isn't public.

So for a borderline application it's worth comparing several banks at once, rather than relying on one. What banks accept as income is covered on the Which income a bank will accept page.

What can you do about it?

Three things, and all of them act on the same ratio.

• Close loans you don't use. A credit card counts towards your repayments even when undrawn, because the bank works with the limit, not the current balance.
• Document income you forgot about. A parental allowance, rental income or a service pension are often counted.
• Extend the term. A lower repayment improves the ratio, but you'll pay more in interest. It's a trade-off, not a trick.