Your old employer can cost you €31,065 of flat tax

A developer resigns in March, opens a partita IVA the week after, and keeps invoicing the company they left. For the rest of that year Italy’s flat tax applies as usual. From the following January it does not, and on €50,000 of billing that costs €10,355 a year. The regime stays shut for three tax years, not the two the lookback period suggests: €31,065 before they can use it again.17

None of that follows from resigning. It follows from who she bills afterwards, and it can be avoided by billing someone else — which is the part of the rule most worth understanding before signing the first contract.

What the rule actually bars

The flat-rate regime lists the people who cannot use it, and one of them is defined by their client list. Letter d-bis) excludes “le persone fisiche la cui attività sia esercitata prevalentemente nei confronti di datori di lavoro con i quali sono in corso rapporti di lavoro o erano intercorsi rapporti di lavoro nei due precedenti periodi d’imposta, ovvero nei confronti di soggetti direttamente o indirettamente riconducibili ai suddetti datori di lavoro” — people whose activity is carried on mainly towards employers they work for, or worked for in the two preceding tax years, or towards anyone traceable back to those employers.1

Three things in that sentence do the work. The bar attaches to the share of the activity, so a former employer can be a client and cannot be the main one. The window reaches back two tax years, so the person who left a job in 2026 is still inside it in 2028. And the last clause follows the money through intermediaries: an agency, a subsidiary or a holding company that ends up paying for the same work is treated as the employer.1

Nothing in it is about the type of work. A designer who leaves an agency and does entirely different work for it is caught; one who does identical work for a competitor is not.

Two years of lookback, three years out

The obvious reading of a two-year window is that the regime is unavailable for two years. The statute says otherwise, in a separate provision. Comma 71 provides that the regime “cessa di avere applicazione a partire dall’anno successivo a quello in cui … si verifica taluna delle fattispecie indicate al comma 57” — it stops from the year after the one in which the cause arises.2

Put the two together and each year inside the lookback window shuts the year after it. For someone whose employment ended in 2026 the cause arises in 2026, in 2027 and again in 2028, because 2026 is still one of the two preceding tax years each time. Those three verifications close 2027, 2028 and 2029.

Comma 57 can also be read the other way — as a direct bar in the year the cause arises, rather than in the year after it. On that reading the years lost are 2026, 2027 and 2028. The count is the same either way, which is why the three-year figure survives the disagreement: the two readings differ about which January the regime comes back, not about how many are missed.

The run is only as long as the client mix keeps it going. If the old employer stops being the largest client during 2026, the cause is made out once and the regime is unavailable for a single year. Three years is what happens when the arrangement simply continues.7

What the three years cost

A person outside the regime files under the ordinary rules: IRPEF on actual profit at progressive rates, plus the regional and municipal surcharges, in place of a single substitute tax on a statutory share of billing.64 Contributions to the INPS Gestione Separata are the same on both sides, so the whole difference is tax.5

At €20,000 of billing a year outside the regime costs €2,952; at the €85,000 ceiling it costs €21,620. The gap widens with billing because the flat rate does not move and the progressive scale does.7

It also depends on which profitability share the activity code carries, since that share decides how much of the billing the flat rate taxes at all. The bands that presume the least profit lose the most by leaving.

Real business costs narrow it, because the ordinary rules deduct them and the flat rate never does. At costs of 10% of turnover the €50,000 practice loses €7,656 a year instead of €10,355; at 20% it loses €4,957, and at 30% €2,471. The point where the two regimes leave the same money is 40.6% of turnover for this band at this billing, which an earlier piece measured across the whole grid.8

The start-up rate makes it worse, and may not be there

A new practice pays 5% instead of 15% for its first five years, which raises what a lost year costs the €50,000 consultancy to €12,831, and the three years to €38,493.7

Whether that rate was ever available is a separate question with the same answer at its root. Comma 65 grants it only if the activity “non costituisca, in nessun modo, mera prosecuzione di altra attività precedentemente svolta sotto forma di lavoro dipendente” — provided it is in no way a continuation of work previously done as an employee.3 The same career move that triggers the client-mix bar is the one that puts the start-up rate in doubt, so the person most likely to be reading about d-bis is often the one who should not have counted on the 5% either.

The word the statute never defines

The condition turns on the activity being carried on prevalentemente towards the former employer. The provision states no percentage, and neither does any other comma of the regime.1 That is unusual inside this particular text: the same set of commi fixes the ceiling at 85,000 euro, the immediate exit at 100,000, the staff-cost limit at 20,000 gross and the employment-income bar at a stated figure. Every other limit is a number. This one is an adverb.4

The consequence of drafting it that way is that the person has to judge their own year against a word, and can only do it once the invoices have gone out. Someone who takes one more job from an old employer in December may have changed their tax position for the following year, and nothing in the statute told them where the line was.

What this does not settle

Four things. Every figure here assumes no deductible business costs unless the sentence says otherwise, and the cost ladder above is the sensitivity that matters most. Contributions are Gestione Separata in every row, so the table of profitability shares reads as the same professional under a different presumed-profit share rather than as a shop or a building firm, which would pay artisan or trader contributions instead.

The regional and municipal surcharges vary by where you live and the engine applies a single representative pair, so the ordinary-rules side moves by some hundreds of euro between addresses. And the reading of when the bar starts is the statute’s own sentence, not a ruling: this piece reports what commi 57 and 71 say and how many years follow from them, and the answer to whether a particular contract is caught depends on facts the text alone cannot supply.

What the arithmetic does not decide either is whether the regime was worth keeping. A person offered enough additional work by a former employer is better off outside the flat rate than inside it with a smaller book, and the €85,000 ceiling makes the same point at the other end of the scale.