Portugal's Top-Up Property Tax (AIMI) Passes 100,000 Payers for the First Time as Individual Owners Jump 22%

Portugal's top-up property levy has crossed a symbolic line. More than 101,000 taxpayers were billed for the Adicional ao Imposto Municipal sobre Imóveis (Additional to the Municipal Property Tax, known as AIMI) in its latest cycle — the first time the figure has cleared 100,000 since the tax was created, according to official data reported this week.

The headline number is 101,820 taxpayers, up 8.9% on the previous year and the steepest annual rise recorded since AIMI was introduced in 2017. Between them, those taxpayers owned around 613,000 properties caught by the surcharge.

Families, not companies, drive the increase

The most striking shift is who is being pulled into the net. The number of individuals paying AIMI rose by roughly 22%, far outpacing the near-6% increase among companies. Businesses still shoulder the larger share of the bill overall, but the growth is now coming from households — a sign that climbing property values are dragging ordinary owners across thresholds that were once the preserve of large portfolios.

That is the mechanical effect of a buoyant market. AIMI is charged on the combined Valor Patrimonial Tributário (Taxable Asset Value, or VPT) of a person's residential properties and building land held on 1 January each year. As the tax authority reassesses values and as prices rise, more owners breach the entry point even without buying anything new.

How the surcharge works

For individuals, the first €600,000 of combined taxable value is exempt. Above that, the rate is 0.7% on the slice between €600,000 and €1 million, 1% between €1 million and €2 million, and 1.5% on any value beyond €2 million. Married couples and civil partners who file jointly can pool their allowance, shielding the first €1.2 million.

Companies pay a flat 0.4% on the total taxable value of their residential holdings, with no exemption, though properties used as the personal residence of directors are taxed at the individual marginal rates. Premises classified as commercial, industrial, services or "other" fall outside the surcharge entirely.

For foreign residents and investors, the practical takeaway is the €600,000 line. A single high-value apartment in Lisbon or Cascais, or a couple of mid-range homes held in one name, can be enough to trigger a bill — and the joint-filing option can roughly double the cushion for couples. The charge is billed in September, separately from the standard IMI that lands earlier in the year.

Where the money goes

Unlike ordinary IMI, which funds municipalities, AIMI revenue is earmarked for the Fundo de Estabilização Financeira da Segurança Social (Social Security Financial Stabilisation Fund, or FEFSS), the reserve that backstops the state pension system. With the payer base now past 100,000 and widening fastest among individuals, the surcharge is quietly becoming a more meaningful contributor to that fund — and a growing line item for a broader slice of property owners than its designers originally had in mind.