Compound interest calculator
Calculate compound interest: final value, interest earned and capital growth. Free calculator with monthly, quarterly and yearly compounding.
Savings
Calculator · Savings
Treasury bonds calculator
Calculate the return on State Treasury bonds. Enter the amount, bond type and term — the calculator works out gross interest, Belka tax and net return.
How we calculate the bond return
Interest = face value × rate. Belka tax = interest × 19%. Net return = interest − tax. Inflation bonds: rate = inflation + margin.
Example: 3-year bonds, 10 000 zł, interest 6.5%
Year 1: interest 650 zł, tax: 123,50 zł. Net return year 1: 526,50 zł.
Frequently asked questions
What are treasury bonds?
They are debt securities issued by the State Treasury — you lend money to the state and receive interest in return.
Are treasury bonds safe?
They are considered very safe, as repayment is guaranteed by the State Treasury, though the return is usually modest.
What is an inflation-indexed bond?
Its interest equals current inflation plus a fixed margin, protecting your savings against rising prices.
Is bond interest taxed?
Yes, interest is subject to the 19% Belka capital gains tax, deducted at payout.
Can I sell bonds early?
Yes, you can redeem most bonds early for a small fee that reduces the accrued interest.
How do I buy treasury bonds?
You can buy them online or at selected banks; details are available on obligacjeskarbowe.pl.
Indicative result
Result is indicative. A variable rate may differ from the assumed one. Check on obligacjeskarbowe.pl.
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