Italy IMU Calculator: Imposta Municipale Unica on Property
Work out the Italian IMU (Imposta Municipale Unica) on a property — the municipal property tax — from its taxable base and your comune's rate, and the base net of the tax.
Adjust the inputs and select Calculate for a full breakdown.
Compare Common Scenarios
How the numbers shift across typical situations for this calculator:
| Scenario | IMU due | Taxable base after IMU |
|---|---|---|
| 1.06% of €100,000 (€1,060) | 1,060 | 98,940 |
| 0.86% of €120,000 | 1,032 | 118,968 |
| 1.06% of €80,000 | 848 | 79,152 |
| 0.76% of €150,000 | 1,140 | 148,860 |
How This Calculator Works
Enter the IMU taxable base (base imponibile) and your comune's rate (aliquota). The calculator returns the annual IMU due. The taxable base for a building is the revalued cadastral income (rendita catastale × 1.05) times the category coefficient (e.g. 160 for most homes); once you have the base, IMU is simply that base × the municipal rate.
The Formula
Percentage of an Amount
Amount is the base value, Percentage is the rate applied to it
Worked Example
At an aliquota of 1.06% on a taxable base of €100,000, the IMU is €1,060 for the year. IMU is Italy's main municipal property tax, payable by owners of buildings, building land and (in cases) agricultural land. Crucially, it generally does not apply to the main home (abitazione principale) unless it's a luxury category (A/1, A/8, A/9) — so it mainly hits second homes, rented properties, land and commercial premises. The rate is set by each comune within national limits, and the tax is paid in two instalments (June and December).
Key Insight
IMU is the central recurring property tax in Italy, and getting it right means understanding both the base and the rate. The taxable base (base imponibile) is the part people find fiddly: for an ordinary home you take the rendita catastale (the cadastral income from the Catasto), revalue it by 5% (× 1.05), then multiply by a coefficient that depends on the cadastral category — 160 for most residential (group A except A/10), with different multipliers for offices (80 for A/10), shops, and other categories; agricultural land uses the reddito dominicale × 1.25 × 135. Once you have that base, IMU is just base × the comune's aliquota, which this calculator computes. The rate (aliquota) is set locally within state-defined limits — the standard reference ceiling is 1.06% for most properties (a comune can raise it slightly under specific rules or lower it, and set different rates for different property types), so the same base yields different tax depending on the municipality. The big exemption: your main home (abitazione principale) is generally IMU-free unless it falls in a luxury cadastral category (A/1 stately homes, A/8 villas, A/9 castles), in which case IMU applies with a reduced rate and a fixed detrazione. Reductions exist too — for example 50% of the base for properties granted in use (comodato) to close relatives under conditions, for historic/uninhabitable buildings, and a reduced rate for properties rented at the canone concordato. Ownership and time matter: IMU is split by ownership share and by the months of possession in the year (a month counts if owned more than half of it). Payment is in two tranches — acconto by 16 June and saldo by 16 December. This calculator handles the final step (base × rate) and the proration/exemptions are up to you; for an exact figure, compute the base from the rendita, apply your comune's aliquota, prorate by share and months, and apply any reduction or main-home exemption.
From rendita catastale to base imponibile: the practical formula
The single most asked question in the IMU SERP is 'how do I get from the cadastral income to the tax I owe?'. The answer is two steps. First, find the rendita catastale (cadastral income) for the property — it appears on your visura catastale, on the deed (rogito), or on prior F24 forms. You can pull a visura for your own property free of charge from the Agenzia delle Entrate's online services with SPID, CIE, or CNS.
Second, apply the IMU formula: base imponibile = rendita catastale × 1.05 × coefficiente di categoria. For ordinary residential (groups A excluding A/10) the coefficient is 160. So a rendita of €600 gives a base of 600 × 1.05 × 160 = €100,800. IMU due is then base × your comune's aliquota, which is what this calculator computes.
Other coefficients to know: A/10 offices use 80; B (uffici pubblici, scuole) use 140; C/1 (negozi) use 55; C/2, C/6, C/7 (magazzini, garage) use 160; D (industriali, alberghi) use 65; agricultural land uses reddito dominicale × 1.25 × 135. Match the coefficient to the cadastral category to get the right base.
Who pays IMU, who doesn't, and the second-home reality
IMU's defining exemption is the abitazione principale (primary residence) — your registered home, used by you and your family, is exempt unless it falls in luxury categories A/1 (case signorili), A/8 (ville), or A/9 (castelli, palazzi storici), which pay IMU at a reduced rate with a fixed €200 deduction (detrazione). For everyone else, the second home and its variants are where IMU bites hardest.
Common second-home situations and what to apply: a free-use second home (a disposizione) pays the full ordinary rate (usually 0.86%–1.06% by comune). A rented second home pays the same ordinary IMU unless your comune grants a reduced rate for canone concordato leases — frequently around 0.76%, sometimes lower. A property granted in comodato to a parent or child (with strict conditions and a registered contract) qualifies for a 50% reduction of the base imponibile in many comuni. Properties classified as historically valuable or formally uninhabitable (inagibili, inabitabili) also get the 50% base reduction.
Proration is critical for the actual bill. IMU is owed in proportion to your ownership share (quota di possesso) and the months of possession in the year — a month counts if you owned the property for more than half of it. Buy in mid-May and sell in mid-October: months 6, 7, 8, 9 plus partial credit for May/October decide what you pay.
Paying IMU: F24, ravvedimento operoso, and the rate-change gotcha
IMU is paid in two instalments via Modello F24: acconto by 16 June (50% of the prior year's total, using the prior year's aliquote) and saldo by 16 December (conguaglio with the current year's aliquote, which the comune typically publishes by end-October). Each comune has its own tributo codes for IMU on second homes, rented properties, fabbricati produttivi etc. — they go in the Sezione IMU e altri tributi locali of F24.
If you miss a deadline, ravvedimento operoso lets you self-correct with reduced sanctions: 0.10% per day for the first 14 days, 1.50% from day 15 to 30, 1.67% within 90 days, 3.75% within one year. Interest accrues at the legal rate. Always preferable to waiting for the comune to assess and apply the full 30% sanction.
The aliquote gotcha: comuni often raise rates mid-year. Because the acconto uses prior-year aliquote and the saldo settles at current-year aliquote on the full annual amount, the December payment can be sharply larger than the June one. Check your comune's IMU page (or the MEF Portale del Federalismo Fiscale) for the current year's deliberation before computing the saldo.
IMU on a second home — what you pay for typical rendite
Rendita catastale × 1.05 × 160 gives the base imponibile for ordinary residential property. Below are the IMU bills at three common comunal aliquote: 0.86% (many medium-sized comuni), 1.06% (the statutory ordinary ceiling many capitals apply), and 0.76% (commonly used for properties at canone concordato).
| Rendita catastale | Base imponibile (× 1.05 × 160) | IMU @ 0.76% | IMU @ 0.86% | IMU @ 1.06% |
|---|---|---|---|---|
| €400 | €67,200 | €511 | €578 | €712 |
| €600 | €100,800 | €766 | €867 | €1,068 |
| €800 | €134,400 | €1,021 | €1,156 | €1,425 |
| €1,000 | €168,000 | €1,277 | €1,445 | €1,781 |
| €1,500 | €252,000 | €1,915 | €2,167 | €2,671 |
Figures are for a full year and 100% ownership. Multiply by your possession share and prorate by months. For an A/1, A/8 or A/9 main home, also subtract the €200 detrazione.
Frequently Asked Questions
How is IMU calculated?
Multiply the taxable base (base imponibile) by your comune's rate (aliquota). At 1.06% on a base of €100,000, the IMU is €1,060. The base itself comes from the revalued rendita catastale (× 1.05) times the category coefficient — compute that first, then apply the municipal rate.
What is IMU?
Italy's Imposta Municipale Unica — the main municipal property tax, paid by owners of buildings, building land and certain agricultural land. It's set by each comune within national limits and paid in two instalments (June and December). The main home is generally exempt unless it's a luxury category.
How is the taxable base worked out?
For an ordinary home, take the rendita catastale, revalue it by 5% (× 1.05), then multiply by the category coefficient — 160 for most residential property, 80 for A/10 offices, and other multipliers for other categories. Agricultural land uses the reddito dominicale × 1.25 × 135. This gives the base you enter here.
Do I pay IMU on my main home?
Generally no — the abitazione principale is exempt from IMU, unless it's in a luxury cadastral category (A/1, A/8, A/9), where IMU applies at a reduced rate with a fixed deduction. So IMU mainly affects second homes, rented properties, building land and commercial premises rather than your primary residence.
Are there reductions on IMU?
Yes — for example a 50% reduction of the base for homes lent (comodato) to close relatives under conditions, for historic or uninhabitable buildings, and a reduced rate for properties let at the canone concordato. IMU is also split by ownership share and by months of possession in the year, so prorate accordingly.
References & Authoritative Sources
- Ministero dell'Economia e delle Finanze (MEF) — Imposta Municipale Unica — disciplina e modalità di calcolo · consulted May 31, 2026 · Disciplina e modalità di calcolo IMU
- Agenzia delle Entrate — Consultazione delle rendite catastali · consulted May 31, 2026 · Servizio di consultazione della rendita catastale per il calcolo della base
- Legge n. 160/2019 — art. 1, commi 738-783 — Disciplina nazionale dell'IMU dopo l'unificazione (Legge di Bilancio 2020) · consulted May 31, 2026 · Aliquota di riferimento, coefficienti di categoria, esenzioni, riduzioni
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Methodology & Review
The IMU is the municipal rate (aliquota) applied to the property's taxable base (base imponibile); the remainder is the base after the tax. It assumes you've already computed the base imponibile and does not derive it from the rendita catastale, apply the main-home exemption, or prorate by ownership share or months of possession.
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