Offsetting in the F24 form: which credits, which debts, and up to what cap

Elena runs a small furniture company, an SRL based in Verona. In June it owes the corporate income tax balance, the tax withheld from staff wages and the employees' social security contributions, while it sits on a VAT credit of 18,000 €. Can that credit pay everything else? Yes, within precise rules: what may be offset, how much, and through which channel.

One form to pay and to offset

The F24 rests on a simple idea: a single payment covering taxes, contributions and other sums owed to the State, the regions and the social security bodies. Article 17 of Legislative Decree 241 of 1997 adds a facility that businesses value highly: credits arising from tax returns can be used in the same form to settle debts falling due.

To offset is to pay with a credit rather than with money. The debt goes in the column of amounts paid, the credit in the column of credits used, and the bank or the Agenzia delle Entrate, Italy's revenue agency, collects only the difference. When the two match exactly, the balance is zero and no cash leaves the account.

Practitioners separate two forms. Vertical offsetting stays inside one tax: last year's corporate tax credit reduces this year's corporate tax, and a VAT credit lowers the VAT due in later settlements. Horizontal offsetting uses the credit of one tax to pay a different tax, or a social security contribution, and it is the form this course mostly follows.

The legislator built thresholds, deadlines, certifications and checks around the second form, because that is where an inflated or fictitious credit can quietly turn into an unpaid tax. A small business meets it whenever it has a credit to use up and several different debts falling due in the same month.

Which debts and which credits enter the form

Paragraph 2 of Article 17 lists the sums concerned. They include income taxes with their surcharges and the withholdings paid directly, VAT from periodic settlements and from the annual balance, substitute taxes replacing income tax or VAT, the social security contributions of workers and employers, and the premiums owed to INAIL, the workplace injury insurer.

The list goes on with items a small business meets less often: interest due when a tax is paid in instalments, government licence fees, school fees and other revenues designated by ministerial decree. The law ties the two operations together, so anything paid through the unified form can also be settled with an eligible credit.

There is one exception inside the list. For withholdings that Presidential Decree 602 of 1973 allows to be paid at the provincial State treasury, choosing that route rules out offsetting. Small businesses rarely use it, but it shows that the F24 is the natural meeting point for debts and credits, and the only one where offsetting works.

A clarification issued in 2023 settled a recurring doubt. Decree-Law 11 of that year interprets the rule as allowing offsetting between debts and credits owed to or by different collecting bodies. A credit held against the State can therefore pay a social security contribution, provided every other rule in force is respected.

Paragraph 1 also sets a time boundary. Eligible credits are those shown in tax returns and periodic reports, and the offset must be made by the filing date of the following return. A forgotten credit does not stay available in the F24 forever: sooner or later it must be spent, or carried into the next return.

Credits held against INPS and INAIL

Social security credits follow their own calendar, set by paragraph 1-bis. For craftspeople and traders registered with the special schemes, and for professionals enrolled in the separate scheme, a credit held against INPS, the national social security institute, can be offset from the tenth day after the income tax return showing it is filed.

For non-agricultural employers the reference point is the monthly transmission of payroll data: the contribution credit may be used from the fifteenth day after that filing deadline. Credits for INAIL premiums can be offset provided they are certain, liquid and payable, and recorded in the insurer's own archives.

This course does not quantify contributions. The rates and amounts owed by self-employed people and by members of the separate scheme are published each year by INPS in its circulars. All that matters here is that such credits may enter the F24 on the timetable above, and that their substance can always be checked later.

The annual cap of 2 million euros

Offsetting has a ceiling. Article 34 of Law 388 of 2000 sets a maximum yearly amount for the tax credits and contributions that may be offset in the F24, and the same ceiling applies to refunds paid to holders of a tax account. The original wording spoke of one billion lire; the figure has since been raised several times.

The update notes in the Official Gazette trace its history. From 2014 the cap stood at 700,000 euros; for 2020 and 2021 it was lifted only temporarily. The 2022 Budget Law, Law 234 of 2021, then set it at 2 million euros from 1 January 2022 onwards, with no end date attached.

The cap runs by calendar year, not by financial year. It adds up the credits and contributions offset in the F24 under Article 17 together with the refunds paid through a tax account, whichever tax they started from. A company whose financial year straddles two calendar years must count from January to December, not along its own accounts.

The counter does not care whether a credit is large or small, or whether it concerns a tax or a contribution: everything offset under Article 17 lands in the same yearly total. Most small businesses stay well below the ceiling; it becomes real for those that steadily build up large credits, VAT credits being the usual example.

Not everything counts towards it. A 2014 simplification decree provided that overpaid withholdings and substitute taxes are deducted from later payments only through the F24, and that those amounts are left out when measuring the Article 34 cap. The rule was written for withholding agents who have paid too much.

What happens beyond the cap? Paragraph 2-ter of Article 17 is blunt: when the credit used exceeds the maximum that may be offset, the F24 is rejected, and the taxpayer is notified of the rejection. A rejected form has no effect at all, so the debts it was meant to settle remain unpaid, with the consequences of a late payment.

The ceiling should be planned rather than discovered in December. A business holding large credits is wise to keep a schedule of every offset made during the year, tax by tax, and to compare the running total with the cap before each new filing. Credit that finds no room in the year is not lost, but needs another route.

The filing channel

Everyone holding a VAT number files the F24 electronically only. When the form carries offsets, the channel narrows further: the agency's information page requires its own online services, F24 web or F24 online through the Entratel or Fisconline credentials, or an authorised intermediary using them. Ordinary home banking is no longer enough.

The requirement covers a precise list of credits: VAT, income taxes and surcharges, substitute taxes, IRAP, credits earned as a withholding agent, tax credits to be reported in section RU of the income tax return, and contribution and premium credits held against INPS and INAIL. Its legal basis is paragraph 49-bis of Article 37 of Decree-Law 223 of 2006.

A second rule applies to every credit, whatever its nature. A zero-balance form, one in which offset credits exactly match the debts, must always be filed through the agency's own online services. The requirement comes from Article 11 of Decree-Law 66 of 2014, which the same information page cites.

One marginal exception survives: for tax credits that may be offset only at the collection agents, the page still accepts a paper form. For an ordinary business the working rule is easier to remember. If a credit appears anywhere in the F24, the form is sent from the agency's reserved area, never from the bank's website.

Filling in the form follows the usual rules. Each tax sits in its own section: Erario for national taxes, Regioni for IRAP and the regional surcharge, and the local taxes section for municipal levies, each with its tax code and a four-digit reference year. Amounts always carry cents, even when the cents are zero.

Credits usable at once and credits that must wait

Paragraph 1 of Article 17 draws a line based on the amount. Annual or quarterly VAT credits, and credits for income taxes and surcharges, substitute taxes and IRAP, may be offset beyond 5,000 euros a year only from the tenth day after the return or application that gives rise to them has been filed.

In practice, the portion of credit within that threshold need not wait for the return, while the portion above it must. The second module comes back to this rule, which for VAT credits is bound up with the certificate of compliance, and to the blocks that can stop offsetting even when the credit itself is sound and available.

Keeping track of every credit

Every credit has a history: the return it comes from, the date from which it can be used, the amounts already spent. Keeping that history in a schedule updated with each F24 tells the business at any moment how much is left, whether the 5,000-euro threshold has been crossed and how much room remains below the annual cap.

The schedule also pays off when the next return is prepared, since the previous year's credit has to be reported together with the amounts offset. A mismatch between what the F24 filings show and what the return declares is exactly the kind of inconsistency worth finding yourself, before an inspector finds it for you.

A useful schedule needs few columns: type of credit, year and return of origin, date from which it can be offset, starting amount, each use with its date and the tax code of the debt paid, and the balance left. A yearly total sits at the bottom for comparison with the cap. Minutes of work that pay off later.