How to Calculate Your Monthly Mortgage Payments

A practical walkthrough of mortgage payment math for Georgian banks — the amortization formula, a worked example, and the costs the formula leaves out.

Most banks in Georgia use equal monthly installments (amortized schedules). If you know your loan principal, the annual interest rate, and the loan term, you can calculate your estimated monthly installment.

Keep in mind that with variable/floating interest rate contracts, your rate is directly pegged to a benchmark index, typically the NBG (National Bank of Georgia) Refinancing Rate. The NBG adjusts this policy rate periodically based on macroeconomic indicators. Consequently, when the central bank alters the refinancing rate, your monthly payment fluctuates accordingly.

Amortization formula

To estimate your monthly payment, financial institutions use a standard amortization formula:

P = L * (r * (1 + r)^n) / ((1 + r)^n - 1)

P — Monthly Payment
L — Total Loan Amount (Principal)
r — Monthly Interest Rate (annual nominal rate divided by 12)
n — Loan Term in Months

A worked example

Suppose you want a mortgage loan of ₾175,000 at an annual nominal interest rate of 12.8% for a term of 20 years (240 months):

Monthly rate: r ≈ 0.01067
Formula coefficient: (1 + r)^n ≈ 12.69
Estimated monthly installment: ≈ ₾2,028

What the formula excludes

This formula only represents the base principal and interest. In reality, a mortgage schedule almost always includes additional monthly or one-off costs:

Insurance premiums — most commercial banks require mandatory property and life insurance, which are billed monthly and increase your cash flow requirements.
Bank fees — one-time loan origination fees, administrative charges, or potential prepayment penalties.
Foreign exchange (FX) risk — if you earn in GEL but borrow in USD/EUR, exchange rate volatility will directly impact your monthly debt burden in local currency.

Our online calculator on Ipotekebi.ge automatically aggregates these ancillary charges, displaying the actual Annual Percentage Rate (APR) to protect you from hidden costs.

Key rules of thumb before borrowing

Comfortable Debt-to-Income (DTI) ratio — ensure your total monthly debt servicing (including the new mortgage and existing loans) does not exceed 30% to 40% of your net monthly income. This keeps your household budget stable.
Financial runway (emergency fund) — a mortgage is a long-term liability. We recommend maintaining a liquid emergency fund covering 3 to 6 months of mortgage payments as a safety net.
Rank by APR, not nominal rates — never select a lender based solely on the advertised nominal rate. Focus on the APR, which factors in all fees and insurance to reflect the true all-in cost of credit.

Use the Ipotekebi calculator

Don't waste time on complex manual calculations, where the risk of error is always high. Open the mortgage calculator, enter your target property value and monthly income, and instantly compare the real terms of leading Georgian banks in one place — completely free.