How to calculate IRC payments on account

What is it for?

During the year, the company pays the State in advance part of the Corporate Income Tax (IRC) it will owe, in three instalments: the payments on account. The amount is based on the previous year's IRC. Odoo calculates the three instalments in the year's Form 22 (Modelo 22), puts them on the tax calendar with their deadline and, at year end, adds up what was paid in field 360 of Modelo 22. Pending validation by a certified accountant: payments on account and field 360 of Modelo 22 (Corporate Income Tax Code (CIRC), art. 104 and 105).

When to use it?

• At the start of the year, once the previous year's Modelo 22 is prepared: to know how much to pay and when.
• When the tax calendar does not show the year's IRC payments on account: they only appear after this calculation.
• Before 15 December, if the year's profit is much lower than the previous year's and the certified accountant decides to reduce or not pay the 3rd instalment.
• It does not apply in the first year of activity: without a Modelo 22 for the previous year there are no payments on account (see “Common problems”).

Where to find it?

• Accounting › Declare › Form 22 (corporate income tax) (in the Corporate income tax group): open the year's Modelo 22; the Calculate payments on account button is at the top and the instalments are on the Payments on account tab.
• Accounting › Declare › What is there to do with the corporate income tax? › Supporting lists › Payments on account of corporate income tax: the list of all instalments. Before the calculation it is blank and has no New button.

Before you start

• Your profile is Accountant (the whole example was done with it).
• The previous year's Modelo 22 exists, with the IRC assessed, the withholdings and the turnover. In the example, the 2025 one of Empresa Demonstração, Lda: tax of 5.136,67 € and turnover of 279.000,00 €.
• For the current year, open Modelo 22 with New: choose the Fiscal Year (2026); the Date From and Date To become 01/01/2026 and 31/12/2026 and the Scheme is set to General regime (the other options are Simplified regime, Group of companies and Collective investment undertaking). Save. The current year's Modelo 22 is provisional until the closing; here it is only used for the instalments. The rest of Modelo 22 (tax adjustments, surcharges, autonomous taxation) has its own article.

How to use it

1. In the 2026 Modelo 22, click Calculate payments on account.
2. Open the Payments on account tab. There is one line per instalment, with Instalment, Due date, Percentage (%), Tax of the reference period, Amount, Payment, Paid and State. In the example:
   • 1st on 31/07/2026, 2nd on 30/09/2026 and 3rd on 15/12/2026;
   • Percentage (%) 80,00 (the 2025 turnover is 279.000,00 €) on the Tax of the reference period of 5.136,67 €;
   • Amount 1.370,00 € each, 4.110,00 € in total: 80 % of 5.136,67 € is 4.109,34 €, and each third (1.369,78 €) is rounded up to the euro.
3. Check the Tax of the reference period against the previous year's Modelo 22: Odoo uses the IRC assessed without the state surcharge and minus withholding tax. The Percentage (%) depends on that year's turnover (80 % in the example). Pending validation by a certified accountant: base, percentages, turnover limit and rounding (CIRC, art. 105).
4. Open the tax calendar: the obligations “Pagamento por conta de IRC - 1.ª prestação — julho 2026”, “… 2.ª prestação — setembro 2026” and “… 3.ª prestação — dezembro 2026” now exist, with the same deadlines.
5. To reduce the 3rd instalment, open the 3rd line on the tab and click Reduce the 3rd payment. The Reduce the 3rd payment on account window shows the Amount calculated by the law (1.370,00 €), the New amount and the Reason, with the warning “Reducing too much may bring compensatory interest when the amount left unpaid exceeds 20% of the tax due (CIRC art. 107.º).”. Type the new amount and the reason and click Reduce only on the certified accountant's decision. Pending validation by a certified accountant: reduction or waiver of the 3rd instalment and compensatory interest (CIRC, art. 107).

Expected result

• The Payments on account tab has the three instalments totalling 4.110,00 € and the State of each one as of today: in the example, calculated on 29/10/2026, the 1st and 2nd are Late and the 3rd To pay. The Payments on account of corporate income tax list shows the same three.
• Calculate payments on account makes no journal entry: checked, no new entry in the ledger.
• The tax calendar has the three obligations. Those past their deadline are Late (in the example, July and September).

Important notes

• Paying and recording the payment. The payment is made on the Portal das Finanças with the payment slip. In the accounts, the payment to the State goes to account 241 Imposto sobre o rendimento; then open the instalment and choose it in Payment, so that Paid and field 360 count it. Pending validation on screen: the payment to the State was not booked, so as not to change the October 2026 bank balance used by the bank reconciliation articles.
• Special payment on account. Special payments on account (PEC) from previous years still to be deducted are under What is there to do with the corporate income tax? › Special payment on account, and the Modelo 22 Suggest PEC deductions button proposes the deduction. Pending validation by a certified accountant: current special payment on account regime and deduction of PEC still to deduct.
• Additional payments on account. The state surcharge is not part of the base for these instalments; additional payments on account are a separate Modelo 22 calculation. Pending validation by a certified accountant: additional payments on account (CIRC, art. 104-A and 105-A).

Common problems

“There is no Modelo 22 of the previous period…”

• Symptom: when you click Calculate payments on account, “Invalid Operation” with “There is no Modelo 22 of the previous period (ending on 31/12/2024), so there are no payments on account: the first period of activity has none (CIRC art. 105.º, n.º 1). If the company already existed, open the Modelo 22 of the previous period first.” (in the test, on the 2025 Modelo 22, the company's first).
• What to do: if it is the first year of activity, there are no payments on account. If the company already existed, create the previous year's Modelo 22 with the amounts filed and calculate again.

The payments on account do not appear on the tax calendar

• Cause: Calculate payments on account has not yet been clicked on the year's Modelo 22. The calendar's Generate the obligations does not create them.
• What to do: follow steps 1 to 4.