- An invoice sent to an Italian client as a PDF, outside the Sistema di Interscambio, counts as not issued and is penalised under art. 6 of D.Lgs. 471/1997.
- For a flat-rate invoice that changes nothing in the income declared, the penalty is €250 to €2,000; ravvedimento within 90 days cuts the minimum to €27.78.
- For violations from 1 September 2024, several breaches of the same provision in one tax year can be put right as one penalty: €250 increased by a quarter, then reduced. Twelve invoices cost €34.72 as one penalty and €333.36 one by one.
- The reduction follows the first violation and the single penalty is set per tax year, so an old first invoice or a 31 December boundary raises it; in every case tested at the quarter increase it stays well below the separate total.
A freelancer on Italy’s flat-tax regime spends a few months sending Italian clients invoices as PDF attachments. In law none of them was issued: between parties established in Italy an invoice exists only as an electronic one sent through the Agency’s exchange system, the Sistema di Interscambio, and anything else “counts as not issued”.12
Putting twelve of them right before the tax office notices, within ninety days of the first, costs at least €27.78 an invoice, €333.36 in all. Paid as the single penalty the law allows for mistakes made since September 2024, it costs €34.72, and it does not grow with the number of invoices.34
What one invoice costs
The flat-tax regime frees its members from most of the VAT act, but not from invoicing: “certificazione dei corrispettivi”, documenting what they are paid, is one of the duties it keeps. The invoice is due within twelve days of the operation, which for a service is when the client pays.567
A flat-rate invoice carries no VAT, and the Agency’s own e-invoicing guide classes its lines as “non soggette”, outside the tax. The penalty for not documenting such an operation is 5% of the amount, never less than €300, or a fixed €250 to €2,000 when the violation does not affect how income is worked out either. A flat-rate freelancer is taxed on what is collected, not on what is invoiced, so an invoice sent the wrong way changes nothing in the income declared, provided every euro of it is declared. That puts the case in the fixed band, with a minimum of €250 per invoice.289
Ravvedimento, the correction a taxpayer makes on their own before an inspection begins, reduces that minimum to a ninth within ninety days of the mistake, an eighth within the deadline for the year’s return, and a seventh after that. A ninth of €250 is €27.78.10
Twelve invoices, one penalty
Article 12 of the penalties decree has long punished someone who breaks the same provision several times with a single penalty: the one for the most serious breach, increased by a quarter up to double, and never more than the separate penalties added together. A 2024 decree extended it to ravvedimento for violations from 1 September 2024, with two limits. The single penalty is worked out separately for each tax and each tax year, and the reduction is the one that fits the first violation. Late payments are excluded altogether.31011
For twelve invoices at €250, the single penalty’s minimum is €250 increased by a quarter, €312.50, and a ninth of that is €34.72: €298.64 less than settling them one by one. On 23 October 2026 the Agency created the F24 payment codes for single penalties paid this way, one per tax, from 8960 for IRPEF to 8979. Article 6 is the VAT act’s penalty article, which points to the VAT code, 8965.411
Fixed tier of €250 per invoice (D.Lgs. 471/1997 art. 6 c.2), reduced to a ninth. One by one, each invoice's ninth rounded to the cent and added up. As one penalty, €250 increased by a quarter and reduced by a ninth; with one invoice the single penalty cannot exceed the separate one. All invoices in one tax year, violations from 1 September 2024.43
Waiting longer raises both figures, but the single penalty stays below a ninth of what the separate ones would cost.4
| Reduction | When | One by one | As one penalty |
|---|---|---|---|
| 1/9 | Within 90 days of the first invoice | €333.36 | €34.72 |
| 1/8 | Later, within the year's return deadline | €375 | €39.06 |
| 1/7 | After that | €428.52 | €44.64 |
Fixed tier of €250 per invoice, all twelve in one tax year and put right in the same window. With a single penalty the window is the one that fits the first invoice.410
Where the single penalty stops helping
Because the reduction follows the first violation, an old first invoice drags the rest onto its fraction. One invoice a month through 2026, all put right on 31 December, costs €364.59 one by one, three of them still inside ninety days, and €39.06 as one penalty at the January invoice’s eighth. In every order of the three fractions tested, from two invoices to six, the single penalty came out lower.4
The tax year is a hard edge. Six invoices in December and six in January are two single penalties, €69.44. If an invoice’s amount did bear on the income declared, the 5% band with its €300 floor applies instead: on twelve €2,000 invoices that is €399.96 one by one and €41.67 as one, the same proportion.48
What this does not settle
The figures read the single penalty’s minimum as the most serious minimum increased by the smallest amount the article allows, a quarter. The law also says the single penalty can be worked out with procedures the Agency provides; none of its circolari from 2024 to October 2026 is about this calculation, judging by their titles. At the largest increase the article allows, double, twelve invoices cost €55.56 as one penalty.104
Mistakes before 1 September 2024 are outside the rule. Whether the eighth runs to a return deadline or a year from the mistake, for a flat-rate freelancer who files no VAT return, is not settled here. Nor are the client’s own duty to report an invoice it never received properly, any stamp duty owed on the invoices, or a substitute-tax payment made late, which article 12 excludes from the single penalty.38
Download the penalty figures (CSV)One to 24 invoices sent outside the exchange system, priced one by one and as a single penalty: three ravvedimento windows, the €250 and the 5% tiers, the smallest and largest increase, a year boundary and a spread through 2026.Sources
- 1.Normattiva — D.Lgs. 127/2015, art. 1 (testo in vigore al 26 ottobre 2026): comma 3, tra soggetti residenti o stabiliti in Italia «sono emesse esclusivamente fatture elettroniche utilizzando il Sistema di Interscambio»; comma 6, una fattura emessa con modalità diverse «si intende non emessa e si applicano le sanzioni previste dall'articolo 6» del D.Lgs. 471/1997
- 2.Agenzia delle Entrate — Guida «La fattura elettronica», dicembre 2025: una fattura inviata in forma diversa dall'XML o fuori dal Sistema di Interscambio «si considera non emessa, con conseguenti sanzioni (di cui all'art. 6 del Dlgs n. 471/1997)»; i forfettari indicano la natura «Non soggette - altri casi»
- 3.Normattiva — D.Lgs. 472/1997, art. 12 (testo in vigore al 26 ottobre 2026): comma 1, più violazioni della medesima disposizione punite con la sanzione per la più grave «aumentata da un quarto al doppio», esclusi gli obblighi di pagamento; comma 7, mai oltre la somma; comma 8, in ravvedimento «separatamente per ciascun tributo, per ciascun periodo d'imposta»; per le violazioni dal 1º settembre 2024 (D.Lgs. 87/2024, art. 5)
- 4.TaxCompass dataset — the minimum penalty for putting right one to 24 invoices a flat-tax freelancer sent outside the Sistema di Interscambio, one by one and as a single penalty under art. 12 of D.Lgs. 472/1997, by ravvedimento window, penalty tier and increase, 2026 rules (CSV)
- 5.Normattiva — L. 190/2014, art. 1, comma 59 (testo in vigore al 26 ottobre 2026): i forfetari sono esonerati dagli obblighi del D.P.R. 633/1972 «ad eccezione degli obblighi di numerazione e di conservazione delle fatture di acquisto e delle bollette doganali, di certificazione dei corrispettivi e di conservazione dei relativi documenti»
- 6.Normattiva — D.P.R. 633/1972, art. 21, comma 4 (testo in vigore al 26 ottobre 2026): «La fattura è emessa entro dodici giorni dall'effettuazione dell'operazione determinata ai sensi dell'articolo 6»
- 7.Normattiva — D.P.R. 633/1972, art. 6, terzo comma (testo in vigore al 26 ottobre 2026): «Le prestazioni di servizi si considerano effettuate all'atto del pagamento del corrispettivo»
- 8.Normattiva — D.Lgs. 471/1997, art. 6 (testo in vigore al 26 ottobre 2026): comma 2, documentazione di operazioni «non imponibili, esenti, non soggette», sanzione del cinque per cento dei corrispettivi non documentati, ma «da euro 250 a euro 2.000» quando la violazione «non rileva neppure ai fini della determinazione del reddito»; comma 4, non inferiore a 300 euro
- 9.Normattiva — L. 190/2014, art. 1 commi 54–89 e Allegato 4 (regime forfettario, coefficienti di redditività)
- 10.Normattiva — D.Lgs. 472/1997, art. 13 (testo in vigore al 26 ottobre 2026): un nono del minimo entro novanta giorni, un ottavo, un settimo; comma 2-bis, «Se la sanzione è calcolata ai sensi dell'articolo 12, la percentuale di riduzione è determinata in relazione alla prima violazione»
- 11.Agenzia delle Entrate — Risoluzione n. 38/E del 23 ottobre 2026: codici tributo F24 per la sanzione unica da ravvedimento con cumulo giuridico, da 8960 (IRPEF) a 8979, tra cui 8965 per l'IVA
Every external figure above links to the document it came from. Datasets we produced are downloadable, so the arithmetic is checkable rather than taken on trust.
- €9,756A freelancer who leaves Italy's flat tax by choice for one costly year cannot return for three, and at €50,000 the two years they did not want cost €9,756less take-home over the two extra ordinary years a €50,000 freelancer is held for after opting out of the flat tax
- €508A freelancer who works one year on Italy's flat tax and then leaves pays €508 more tax than one who stays, because the €10,167 of INPS paid after leaving deducts from nothingof flat tax a one-year freelancer billing €50,000 never saves, as the year's INPS is paid after leaving Italy
- €13,263A developer who moves to Italy can bill their old employer abroad on the flat tax, but a job that ends in January instead of December costs the first year: €13,263lost in the first Italian year by a developer billing €60,000 whose job abroad ended in January, not December
- €6,847Bill an Indian client €40,000 on Italy's 5% flat tax and at least €6,847 of the tax it withholds never comes backof €8,000 withheld by an Indian client that the 5% flat tax cannot credit back, on €40,000 of billing
- €400Billing €30,000 in €150 invoices costs €400 in stamp dutya year in stamp duty for a €30,000 practice billed in €150 pieces — 46% of the tax due at 5%
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