IMU 2026: the first instalment on 16 June, who pays and how it is calculated

What IMU is and who has to pay it

Mary has lived in Cinisello since she arrived in Italy, in a flat near the station. Last year her mother passed away and left her the small two-room flat the family kept for guests: since then a new doubt has appeared on her desk. Do you pay for that extra home? And when? The questions we hear most often at our counter start exactly like this, from a transfer of ownership that changes the rules of the game. That is why the first thing we do is not fill in a form: it is working out which properties the tax is really due on.

IMU is the single municipal property tax: a tax on ownership, not on the money you earn. It is paid on buildings, buildable areas and farmland that you own on 1 January of the year. The obligation falls on the owner and on every holder of a right in rem over the property, such as usufruct, use, habitation or emphyteusis; it also covers anyone who has taken the property on lease and the concessionaire of state-owned land. If the home is lent free of charge under a comodato, the tax stays with the owner: the person using it receives no notice. If instead the family home has been assigned by a judge to one spouse after separation, IMU is paid only when the property is a luxury one.

The first instalment on 16 June: how it is calculated

The first instalment of IMU 2026 is called the acconto and is paid by Tuesday 16 June. It is the tax due for the first half of the year, calculated with the rate and the deduction of the previous year: it usually works out at 50% of what is owed for the whole year. The old rates are used because in June many municipalities have not yet approved the new ones, and that is what the law requires. The December balance is the moment when everything is settled: you start again from the tax for the whole year using the 2026 rates, and subtract what you have already paid in June.

• acconto: by Tuesday 16 June 2026, equal to the tax for the first half of the year using the previous year's rules;
• balance: by Wednesday 16 December 2026, the difference between the total tax for the year and the acconto already paid;
• single instalment: if you prefer, you can pay the whole IMU 2026 in one go by 16 June, without waiting for December;
• under 12 euro you pay nothing: if the tax due for the whole year is 12 euro or less, no payment is made;
• no deadline shifts this year: 16 June 2026 falls on a Tuesday and 16 December on a Wednesday, so both payments stay exactly where they are.

Let us take a real example. David inherited a flat in Cinisello with a cadastral income of 500 euro. To find the value the rate is applied to, the income is increased by 5% and multiplied by 160: 500 x 1.05 x 160 = 84,000 euro. With the ordinary rate of 1.06% in our municipality the yearly tax is about 890 euro. In June David pays about 445 euro as the acconto and in December whatever is still outstanding, give or take, since the balance applies the new rates and reflects any change made during the year. If David sells the flat in July, he owes nothing for the second half of the year.

How the taxable base is calculated

The calculation always starts from the cadastral income of the property, the one you find in the cadastral records or in the purchase deed. It is revalued by 5%, multiplied by 160 if it is a home (for other properties the multiplier is different), and then the rate of the municipality where the property is located is applied, not the one where you live. Then the ownership share is taken into account: if the home belongs to two brothers at 50%, each pays their half. And the months are counted: the month in which ownership lasted for more than half of the days of that month counts in full, while the day of the transfer is charged to the buyer.

Who does not pay: exemptions and reductions in Cinisello Balsamo

Almost everyone who comes to our desk starts from the same worry: «do I owe tax on the home I live in?». Usually not: the main residence — the one where you actually live and where you are registered — is exempt, together with one ancillary unit in each of the categories C/2, C/6 and C/7. The luxury categories are the exception: on an A/1, an A/8 or an A/9 the IMU is due. In Cinisello Balsamo the rate for these homes is 0.60%, and the law grants a fixed deduction of 200 euro a year, scaled to the months of ownership.

• not paid: main residence that is not a luxury home (categories A/2, A/3, A/4, A/5, A/6, A/7) and its ancillary units;
• not paid: social housing, flats held in undivided ownership by members of cooperatives, the marital home assigned to a separated spouse, the only property of members of the armed forces, the police forces and the fire brigade, the only property in Italy of pensioners residing abroad and registered with AIRE who have not rented it out;
• not paid: farmland that direct farmers or professional agricultural entrepreneurs own and work themselves, and land in municipalities on small islands or in delimited mountain and hill areas;
• 50% reduction of the taxable base: homes lent free of charge under comodato to parents or children, with a registered contract, if the lender lives and resides in the same municipality and owns only one other residential property;
• 25% reduction of the taxable base: homes rented at a controlled rent under Law 431/1998; a 50% reduction applies to properties of historic or artistic interest, and to those that are unfit for use or uninhabitable and are in fact unused.

Since 2026 the relief for properties that cannot be used has been extended: it now covers not only damage caused by natural disasters, but also buildings rendered unusable by fire, collapse, structural failures or hygiene and health hazards. Watch out: it is not an automatic discount. You need technical documentation stating the condition of the property, a survey by a qualified technician or certification from the municipal offices, and the reduction must appear in the municipality's schedule of rates.

How to pay: F24, tax codes and municipality code

IMU is paid by self-assessment using the F24 form, in the section «IMU and other local taxes». The municipality does not send calculations to your home: it is up to you to do the sums, or to rely on a CAF. Payment can be made at a bank, at a post office, through online banking or with the Agenzia delle Entrate F24 Web. Every amount is rounded to the nearest euro, and the form must be filled in with great care in two fields: the tax code, which changes depending on the type of property, and the municipality code. For properties in Cinisello Balsamo the code is C707: if you get this field wrong, the money ends up in another municipality and you have to ask for a refund.

The main tax codes

• 3912: main residence of luxury type (categories A/1, A/8, A/9) and its ancillary units;
• 3913: farm buildings used as instruments;
• 3914: farmland;
• 3916: buildable areas;
• 3918: other buildings, that is second homes, shops, offices and warehouses;
• 3925 and 3930: group D buildings, with the State share at 0.76% and the municipal share at 0.30%.

What to write on each line

On every line of the F24 you must enter the code of the municipality where the property is located, the reference year, the number of months of ownership, the ownership share and the box showing whether you are paying the acconto, the balance or the whole tax. Anyone filing their income tax return with us receives the form ready to use, with the codes and the year checked: it is the quickest way to avoid mistakes that then take time to put right.

If you missed the June instalment: voluntary regularisation

If the June instalment slipped past you, it is not the end of the world: it can be put right at any time with the ravvedimento operoso (voluntary regularisation), paying the tax, statutory interest and a reduced penalty that grows the more days go by. From 1 January 2026 the statutory interest rate is 1.60% a year and is calculated by days, from the day you should have paid to the day you actually pay. Without regularisation, the ordinary penalty reaches 30% of the amount not paid, on top of the interest.

• within 14 days of the deadline: penalty of 0.0833% for each day of delay;
• from the 15th to the 30th day: penalty of 1.25%;
• from the 31st to the 90th day: penalty of 1.39%;
• after 90 days and within a year: penalty of 3.125%;
• in every case statutory interest calculated by days is added.

Mistakes to avoid and things to check

IMU is a simple tax, but some mistakes come back every year at our desk and they are exactly the ones that then lead to notices and demands. Here are five, in the order in which they most often happen.

• calculating the June acconto with the new rates: you use the previous year's rates, and everything is settled with the December balance;
• forgetting the balance: people who pay the acconto in June often forget that 16 December is just around the corner;
• believing your main home is always exempt: if it is an A/1, an A/8 or an A/9 you pay IMU, even if you live there;
• mixing up the months: anyone who buys or sells part-way through the year is taxed only for the months they really owned the property, and the 200 euro deduction follows the same rule;
• not making use of the reductions: comodato to family members and controlled rent lower the tax, but only with the registered contract and all the requirements in order.

When the IMU return is needed

Usually, if your payments are in order, no return is needed. It must be filed by 30 June of the following year when something happens that the municipality cannot know by itself: a registered comodato contract, a change in the cadastral use, a property taken on lease, bare ownership separated from usufruct. You use the IMU/IMPI or IMU ENC form introduced by the ministerial decree of 24 April 2024. The return also covers the following years, as long as the data does not change.

Where to check your position

The Municipality of Cinisello Balsamo offers two free tools: the online IMU calculation on the municipality's website, which also prepares the F24 for printing, and the LINKmate online desk, accessible with SPID or CIE, where you can see your tax position. Watch out: the database may not be updated in real time, so always check that the data matches the real situation. If something does not add up, the quickest step is to bring your cadastral record and last F24 to our patronato and take stock together.

Questions we are asked most often

The answers to the five questions about IMU that reach our counter most often. If yours is not here, call us or write to us on WhatsApp: the first consultation is free.