Methodology

Investment income is taxed at a flat 28%. You can also add it to your other income at the progressive IRS (income tax) rates: the simulator doesn't calculate that option. Nor does it calculate gains on securities held under a year by people in the top tax bracket.

Returns are assumed to be the same every year. They're assumptions for comparing, not forecasts: in real life, they change from year to year. Fund management fees are already taken out of the returns used.

Amounts are calculated without rounding, then rounded for display.

World-equity index fund (ETF): −1%, 6% and 9% per year. The median is based on the MSCI World index in euros: 6.68% a year from end-2000 to October 2026, through two crashes, minus about 0.2% in fees. The pessimistic one always includes a loss: between 2001 and 2009, this index lost up to 53.6%. The scenarios in ETF key information documents aren't used: they're based on the last ten years, which were very good for shares.

PPR: 0.4%, 1.5% and 2.7% per year. These are the bottom quarter, the median and the top quarter of the 5-year annual return of 81 PPRs, published by APFIPP (the Portuguese funds association) on 6 November 2026. The gap mostly comes from the funds: cautious PPRs, mainly in bonds, earn less than more dynamic PPRs, with more shares.

Certificados de Aforro (base rate, without the loyalty bonus): 0%, 2.14% and 2.50%. The base rate follows the 3-month Euribor, between 0% and 2.50%. Pessimistic: from 2015 to 2022, Euribor was negative, so the base rate was 0% and only the bonus earned anything. Median: 2.14%, the Euribor median since 1994 (ECB). Optimistic: the 2.50% cap.

Term deposit: 0.1%, 1.77% and 3.6% per year. These are the average rates on new household term deposits, published by Banco de Portugal since 2003: about 0.1% from 2019 to 2022, 1.77% as the median, 3.6% in 2007 and 2011.

A projection lasts several years, sometimes decades, and these rates move in the meantime: the 3-month Euribor was above 4% in 2008 and negative from 2015 to 2022. Keeping today's rate would mean assuming it never moves. The median gives a more representative level; the pessimistic and optimistic scenarios show what happens if rates stay low or high.

Every three months, each subscription gets a quarter of its annual rate. The 28% tax is withheld and the rest is added to the capital. The quarter in progress when you withdraw earns nothing.

The base rate follows the 3-month Euribor and changes every month; the simulator keeps it constant. A subscription under three months old can't be withdrawn yet: it counts at its original value. After 15 years, a subscription is repaid and earns nothing more. Minimum: €100 for the first subscription, then €10 per subscription.

Most term deposits don't let you add money during the year. So your monthly contributions wait without interest, then join the deposit at each renewal. Deposits are guaranteed up to €100,000 per person and per bank.

Withdrawal under the legal conditions: the gain is taxed at only 8%. The simulator uses one condition, being 60; each contribution must then be at least 5 years old. But 5 years after the first contribution, the whole PPR can come out under these conditions if at least 35% of contributions were made in the first half of the contract, which is the case with regular contributions. The other legal conditions (retirement, long-term unemployment, serious illness, disability, main-home mortgage) aren't calculated.

Withdrawal outside the conditions: the gain is taxed at 21.5% (8.6% if the contract is over 8 years old, 17.2% between 5 and 8 years, under the same 35% rule). You also pay back the tax reductions already received, plus 10% per year elapsed. The law counts "each year or part of a year" since the year of the reduction; since this count is uncertain, the simulator takes the most cautious option: the year of the reduction counts in full.

When the withdrawal is outside the conditions, the PPR card also shows what would be left if the money stayed invested, with no new contributions, until the first age when withdrawal meets the legal conditions: 60, or later if the first contribution isn't yet 5 years old. The calculation uses the same scenario.

When you sell, the total gain is taxed at 28%. Purchases at a loss offset those at a gain, and there's no tax if the total is a loss. Since 2024, the law lowers the tax on gains held over 2 years (25.2%), 5 years (22.4%) or 8 years (19.6%). It's not yet clear whether this applies to foreign ETFs bought through foreign brokers: so the main calculation stays at 28%, and a box shows what the reduction would give.

ETF: 0.20% a year, according to the key information document of the iShares Core MSCI World (September 2026), with no entry or exit fee. Brokerage fees depend on your broker: €0 by default, adjustable in the simulator.

PPR: 1% a year, a provisional value to be checked. The official CMVM comparison tool, which publishes each PPR's ongoing charges, was unavailable at the time. A non-official source (Literacia Financeira, November 2026) gives a median management fee of about 0.8% a year, and ongoing charges from under 0.5% to over 3%. APFIPP returns are already net of fees: so this value doesn't change the amounts, only the return before fees and the total fees shown.

Fees paid: each month, the gap between growth at the market return and growth after fees, plus purchase fees. Purchase fees reduce the amount invested; for tax, they're part of the purchase price.

Calculation: the year's gain, before tax and after fees, divided by 12, compared with the monthly contribution. The yearly average also works for investments that pay interest every three months or once a year.

Example: €10,000 at the start and €200 a month in an ETF at 6% a year. Year 8 earns €2,209, or €184 a month; year 9 earns €2,486, or €207 a month. So the tipping point is year 9.

If it doesn't come within the chosen term, the site shows the year it would come by continuing the same contributions at the same return, up to 80 years or the investment's maximum term.

The “Export my chart” button on the Budget page creates the image of the diagram in your browser. Your budget isn't sent to any server and no link contains your amounts: on a phone, the image opens in your device's share sheet, and you choose where it goes.