Changing corporate tax advance payments in Bulgaria

Corporate income tax advances in Bulgaria are set in spring from a forecast of the current year's profit. When it becomes clear by autumn that profit will be lower or higher, the company can change the remaining advances with a declaration under Art. 88 of the Corporate Income Tax Act (ЗКПО). The deadline is 15 November; in 2026 it falls on Monday, 16 November.

Who pays advance payments

Advances are based on a forecast of the current year's taxable profit (Art. 83, para. 1 of the Corporate Income Tax Act), not on last year's profit. Whether a company pays advances, and how often, depends on its net sales revenue for the year before the preceding year. For 2026 that is 2024.

The thresholds in the Act are still in leva. Since the euro was introduced they apply converted at the fixed rate of BGN 1.95583 per euro (Arts. 11-13 of the Act on the Introduction of the Euro).

Newly incorporated companies pay no advances for the year of incorporation or the following year, unless they were formed by a transformation (Art. 83, para. 2, item 2). A company without the obligation may pay quarterly advances voluntarily, and then no Art. 89 interest applies (Art. 83, para. 3).

The amount follows from the forecast and the 10% rate (Art. 20):

• 01Monthly advance: forecast taxable profit divided by 12, times 10% (Art. 86).
• 02Quarterly advance: forecast taxable profit divided by 4, times 10% (Art. 87). There is no fourth-quarter advance (Art. 90, para. 2), so the three advances cover 75% of the forecast tax.

Advances are declared with an Art. 87a declaration between 1 March and 15 April of the same year. It is filed even when the forecast is zero or a loss, if the company is required to pay advances; the advance is then zero.

Advance payment deadlines in 2026

The deadlines are in Art. 90 of the Corporate Income Tax Act. When a deadline falls on a non-working day, it moves to the next working day (Art. 22, para. 7 of the Tax and Social Insurance Procedure Code, ДОПК):

How to change advances: the Art. 88 declaration

Art. 88, para. 1 of the Corporate Income Tax Act lets a company file, by 15 November, a declaration to reduce or increase its advances "when it considers that they will differ from the annual corporate tax due". The law sets no minimum difference and asks for no justification, and the declaration is optional, except after a company transformation (Art. 88, para. 3).

• 01The change applies after the declaration is filed (Art. 88, para. 2). Advances whose due date passed before filing are not changed: for quarterly payers, an autumn declaration changes only the third-quarter advance, due 1 December.
• 02For monthly payers, a declaration filed by 16 November 2026, the due date of the November advance, can change the November and December advances. On the form you mark both months, even if one does not change.
• 03You may file more than one declaration. Form 1020 itself gives an example with two change declarations in one year.
• 04In Part IV of the form you mark every remaining month or quarter and enter the new advance. For periods you do not change, you repeat the current amount.

The declaration uses form 1020 (the declaration under Art. 87a and under Art. 88 of the Corporate Income Tax Act), published in State Gazette No. 22 of 2026. It is filled in euro and cents and filed only online, with the qualified electronic signature (КЕП) of the company's representative or an authorised person, through the portal of the National Revenue Agency (NRA, НАП). There is no fee. File a few days before the deadline and check your portal access in advance.

Interest on underpaid advances

Interest under Art. 89 of the Corporate Income Tax Act is due when the determined advances for the year turn out too low. The test is made in the annual tax return:

• 01Determined advances are the amounts under Art. 86 or 87 declared under Art. 87a for the periods before an Art. 88 declaration, and the amounts in that declaration for the periods after it (Art. 89, para. 4). So an increase under Art. 88 also reduces the interest.
• 02Interest runs from 16 April to 31 December of the year (Art. 89, para. 5), whenever the tax is actually paid.
• 03The rate is the European Central Bank (ECB) main refinancing operations rate in force on 1 January or 1 July respectively, plus 8 percentage points (Council of Ministers Decree No. 426 of 2014, as amended in State Gazette No. 115 of 2025, in force from 1 January 2026). For 2026 it is 10.15% until 30 June and 10.40% from 1 July.
• 04Separately from Art. 89, late-payment interest runs on any determined advance not paid by its due date (Art. 9).

Overpaid advances carry no interest or penalty. The annual tax is paid by 30 June of the following year after deducting the advances paid (Art. 93, para. 1), and the overpayment is refunded or offset on request in the annual return (Arts. 128-130a of the Tax and Social Insurance Procedure Code). The same statutory interest rate applies to overdue invoices; how it is calculated is covered in late payment interest in Bulgaria.

Example: quarterly advances and lower profit

Primer EOOD had net sales revenue of BGN 520,000 (€265,871.78) in 2024, so it pays quarterly advances in 2026. In its Art. 87a declaration it forecast 2026 taxable profit of €120,000.00, giving advances of €3,000.00 each (€120,000.00 / 4 × 10%). The first two are paid. In October a large client ends its contract, and actual profit for the year will be around €40,000.00, with tax of €4,000.00.

After the change the determined advances are €6,000.00. Interest would arise only if 75% of the annual tax exceeded €7,500.00 (€6,000.00 × 125%), that is with tax above €10,000.00 and profit above €100,000.00. If profit still reaches €110,000.00, the tax is €11,000.00 and interest is due on €750.00 (€8,250.00 - €7,500.00): €750.00 × 10.15% × 76/360 + €750.00 × 10.40% × 184/360, about €55.94, counting 76 days from 16 April to 30 June and 184 days from 1 July to 31 December. The remaining €5,000.00 of tax is paid by 30 June 2027.

The opposite case: a company declared advances of €1,000.00 (a €40,000.00 forecast), but profit will be around €120,000.00 (tax €12,000.00). Without a change, interest is due on €5,250.00 (€9,000.00 - €3,750.00), about €391.56 for 2026. With an Art. 88 declaration raising the third-quarter advance to €5,200.00, the determined advances become €7,200.00 and no interest is due (€9,000.00 - €9,000.00 = €0.00).

What changes from 2027

The draft amendments to the Corporate Income Tax Act published for consultation on 23 September 2026 do not change the advance payment rules in Arts. 83-91. They propose carrying tax losses forward for up to 10 years, but deducting at most 70% of the year's positive tax result. If adopted, this will affect the 2027 forecast that companies with losses carried forward declare by 15 April 2027. The draft is not yet law; more in Bulgaria tax changes 2027.

Common mistakes

• 01Looking at the previous year's revenue. The advance regime depends on net sales revenue for the year before the preceding year (Art. 83, para. 2, item 1 and Art. 84): for 2026 that is 2024.
• 02Using a 20% tolerance. Since 2021, interest is due on the excess over 25% (Art. 89, para. 1).
• 03Expecting the third-quarter or December advance on 15 December. Both are due on 1 December (Art. 90).
• 04Expecting the declaration to change advances already due. The change applies only after filing (Art. 88, para. 2).
• 05Calculating interest at the old Bulgarian National Bank base rate plus 10 points. Since 1 January 2026 the base is the ECB rate plus 8 points.
• 06Leaving the filing to the last day. The declaration is filed only online with a qualified electronic signature, so check your NRA portal access in advance.

In smetni.app

In the Declarations module (Business plan), the "Annual return" tab shows the advance payment regime, worked out from the net sales revenue in the ledger for the year before the preceding year, and the advance schedule based on the forecast taxable profit you enter. The calculation needs accounting enabled and covering the year before the preceding year. The schedule follows one forecast for the year and does not show an Art. 88 change for individual periods. Advances paid are filled in from bank payments placed in Bank as a corporate tax advance, or typed in. The app does not file the Art. 88 declaration or remind you of the deadline: you file it in the NRA portal. See the guides to declarations and accounting, and plans and pricing.