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Calculadora Capital

Term Deposit Calculator

A term deposit earns a fixed rate over a fixed period, but the interest is taxed. Use the simulator to see, in seconds, how much you actually receive (after the 28% withholding tax) at the end of the term.

Defaults to 28% (mainland Portugal withholding tax). Adjust for Madeira/Azores or for tax aggregation.

Value at maturity
€10,216.00
Net interest
€216.00
Gross interest€300.00
Tax withheld−€84.00

Educational estimate, not financial advice. Rates and taxation may vary.

Video: how to use the calculator

What a term deposit is

It is a savings product where you hand the bank an amount for a fixed term (say 6, 12 or 24 months) at a gross annual rate (TANB) known up front. At the end of the term you get your capital back plus interest. It is one of the most widely used capital-guaranteed products in Portugal.

How the interest is calculated

Gross interest is pro-rated for the term: Interest = Amount × gross rate × (months ÷ 12). The rate is annual; if the term is shorter than a year, the interest is proportional. The calculator uses this convention, the same one banks use to quote the interest on a fixed term.

The 28% tax on interest

Deposit interest is capital income (IRS Category E) and is taxed at source at a flat rate of 28% on the Portuguese mainland. The bank withholds the tax and credits you the interest net. What matters for your savings is therefore the net interest, not the gross, and that is what the simulator highlights.

Worked example

With €10,000 at a gross rate of 3% for 12 months, gross interest is €300. The 28% withholding takes €84, so you receive €216 of net interest and finish with €10,216. For a 6-month term the gross interest would be half (€150).

Frequently asked questions

Is term-deposit interest taxed?
Yes. Interest is taxed at source at 28% (the withholding rate on the mainland). The bank withholds the tax and credits the interest net, so you usually do not need to declare it on your IRS return.
How is interest calculated for a deposit under a year?
Interest is proportional to the term: multiply the annual rate by the fraction of the year. For example, 3% for 6 months equals half: 1.5% on the capital over that period.
Can I pay less than 28%?
Instead of the flat withholding, you can choose to aggregate the interest into your IRS return. It only pays off if your bracket rate is below 28%. Madeira and the Azores apply reduced rates: adjust the tax field in the simulator.

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Sources

Author: Thorben Rasmus Idel · Reviewed by: Nahar Geva · Last reviewed: 2026-05-31