Splitting a firm's profit can cost two partners €7,800

Two professionals who practise through an Italian firm are taxed on its profit in their own hands, share by share, at the ordinary progressive rates. Nothing is taxed at the firm. So the same profit produces a different bill depending only on how the two of them divide it, and on the 2026 rate table that difference reaches €7,800 a year — no more than that, whether the firm makes €100,000 or ten times as much.12

The Agenzia delle Entrate decided on 23 September that the partners who do the professional work may now fix those shares after the year has ended, up to the day the firm files its return. The partner who only put money in still has to have theirs settled before the year begins. For the 2026 tax year those two deadlines are 669 days apart.34

The firm does not pay the tax

Article 5 of the TUIR is the provision that moves the money. The income of a società semplice is imputed to each partner “indipendentemente dalla percezione, proporzionalmente alla sua quota di partecipazione agli utili” — regardless of whether it was actually paid out, in proportion to their share of the profits. A partner owes tax on their share in a year the firm distributed nothing.1

Comma 2 decides what those shares are. Absent a deed, they are presumed proportionate to what each partner contributed; where the value of the contributions is not determined, “le quote si presumono uguali” — equal. A different division has to be recorded in a notarised deed dated “anteriore all’inizio del periodo d’imposta”, before the tax year starts. Signing it in the year, or after it, does not bind that year.1

Each partner then adds that share to their own income and pays IRPEF on it at 23% up to €28,000, 33% up to €50,000 and 43% above. Two people filling those brackets separately is cheaper than one person filling them alone, which is the whole of what follows.2

What the split is worth

Running the rate table over every division of six firm profits gives the range the choice moves within. The equal split is the cheapest one in every row — it is also the division the statute falls back on — and the table reads as the price of moving away from it.11

The spread climbs to €7,800 and then stops. It is reached exactly at a firm profit of €100,000, where an equal split leaves both partners at the top of the second bracket, and it is the same €7,800 at €200,000 and at any figure above. The reason is that it is not really a number about the firm: it is what one partner’s lower brackets are worth against the top rate, which is €28,000 taxed twenty points cheaper plus €22,000 taxed ten points cheaper. A bigger firm does not raise the stake, because there is only ever one set of brackets to lose.211

Between those two ends the choice is often worth nothing at all. At €150,000 of profit every division between a third and two thirds costs exactly €48,900, because both partners are wholly inside the 43% band wherever the line is drawn; at €200,000 that indifference stretches to a seventy-thirty split. The decision bites where one partner is pushed down into the cheaper brackets and the other is not — at €120,000 a seventy-thirty division costs €1,400 more than an equal one, and at €60,000 it costs €1,000.11

What the Agenzia decided this week

Comma 3, letter c) of the same article carries an exception, written for professional associations: they are treated as società semplici, “ma l’atto o la scrittura di cui al comma 2 può essere redatto fino alla presentazione della dichiarazione dei redditi dell’associazione” — the deed may be drawn up as late as the return. Principio di diritto n. 3/2026, published on 23 September 2026, extends that to a società tra professionisti or società tra avvocati constituted as a società semplice.13

The extension carries three limits, and the Agenzia states each one. It reaches only the società semplice form, leaving out “le STP e le STA costituite secondo modelli societari diversi” — an Italian professional firm incorporated as an s.r.l. or an s.n.c. gets none of it. It reaches only “le quote di partecipazione agli utili riferibili ai soci professionisti”. And where the firm has a financing partner, the professionals may divide after the year only what is left once that partner’s share has been fixed in advance under the ordinary rule.3

The reasoning is a split between two purposes. Comma 2’s advance deed exists to stop “arbitraggi nell’imputazione del reddito tra i medesimi soci” — moving the taxable base after the fact onto whichever partner is taxed more lightly. The exception for professional bodies exists because the profit of such a firm turns on personal work that can only be measured once the year has run. Both are in the same article, and the ruling keeps the first for the partner who supplied capital while switching it off for the partners who supplied the work.31

The arithmetic in the table above runs against the stated purpose. A division that tracks who actually billed the year concentrates income on one partner, and concentrating income is the expensive direction under a progressive scale: the cheap division is the flat one the statute already presumes. So the freedom this ruling grants is worth money only when it is used to move a pre-agreed lopsided split back toward the middle, which is the opposite of what the Agenzia says it is for. That tension is not a loophole and nothing here suggests using it as one — the shares still have to answer to “le prestazioni effettivamente svolte”.3

Two deadlines, 669 days apart

Put the ruling beside the filing regulation and the same firm ends up with two dates for the same decision. A financing partner’s share of 2026 had to be in a notarised deed dated before 1 January 2026 — in practice, 31 December 2025. The professional partners’ shares of the same profit may be set up to the close of the firm’s filing window, which for the companies and associations of article 5 runs “tra il 15 aprile e il 31 ottobre dell’anno successivo” — 31 October 2027. The two dates are 669 days apart, and since 31 October 2027 falls on a Sunday the later one can only move further out.43

What this does not extend is anything to do with paying. The filing window is the outer edge of when the deed may be signed; the instalments and balances fall where they always did.4

Why the article never mentions them

Letter c) names “le associazioni senza personalità giuridica costituite fra persone fisiche” and stops. It does not name professional companies because, when the TUIR was approved on 22 December 1986, an Italian professional could not practise through a company at all. That came on 12 November 2011, when article 10 of L. 183/2011 allowed firms for regulated professions to be set up “secondo i modelli societari regolati dai titoli V e VI del libro V del codice civile” — almost twenty-five years after the article that taxes them was written.15

Lawyers waited longer still. Article 4-bis of L. 247/2012 opens the profession to companies of persons, of capital and cooperatives, insists that at least two thirds of the capital and the votes stay with professionals, and holds on to the rule that makes the whole question sensible: “resta fermo il principio della personalità della prestazione professionale”, the work is personal even when the invoice is not. Its text has been in force since 1 January 2018.6

The Agenzia gives the same account of its own silence: the absence of any mention of these firms in article 5 “discende dalla circostanza per cui l’adozione di modelli societari per l’esercizio in forma collettiva delle professioni sia stata consentita solo ad opera della successiva legislazione”. Fifteen years separate the law that created the vehicle from the note that says how an article older than it applies — and the fix is an interpretation, not an amendment, so the text a reader opens still names only associations.3

One consequence sits outside this piece and is worth knowing before anyone joins such a firm: holding a share in an article 5 body is one of the exclusions from the flat-rate regime forfetario, so the partnership and the flat tax do not coexist. We have costed that list separately.7

What this does not settle

Two explanations would have removed the €7,800 if they held, and both were measured rather than assumed. Giving one or both partners income from elsewhere changes where the cheapest division sits — it becomes a band rather than a point — but in none of the configurations run did the spread exceed €7,800. Adding a comune’s two local surcharges does push past it, because several regional scales are bracketed in their own right, so the €7,800 is a ceiling on IRPEF and not on the whole income-tax bill.129

Contributions are absent from every figure above. A professional partner owes them to their own fund — Cassa Forense, Inarcassa, and a dozen others, each with its own rate, floor and ceiling — or to the INPS Gestione separata where no fund covers the activity, and those fall on the same imputed share the tax does. A real bill is larger than these numbers on both sides of the comparison, and which side moves more depends on a fund’s own rules rather than on anything in the TUIR.

Personal reliefs are absent too. The credit for self-employment income under article 13 runs out above €50,000 of total income and depends on each partner’s own position, which no computation from the firm’s accounts can supply. Including it would move the figures; leaving it out keeps every number here derivable from the rate table alone.8

How many Italian professional firms are constituted as a società semplice rather than as an s.r.l. is not in any of these documents, so nothing above says how many firms the ruling reaches. And a principio di diritto is the Agenzia’s reading of the article, issued to keep its own offices consistent. It is not a change to the article, and it does not bind a judge.3