2026 tax deadlines: business calendar

March 2026 update - The 2026 tax deadlines are not just about the May tax package. A company must articulate its VAT, corporate tax, CFE, CVAE, withholding tax and sometimes intra-community declaration obligations all year round. The risk is not just forgetting. The real danger is the gap between obligations, which disrupts cash flow and weakens the compliance of the tax file.

1. Monthly or recurring deadlines

Recurring obligations are those which cause the most cash flow incidents when they are poorly managed.

• ▸DSN: on the 5th or 15th of the month depending on the workforce and payroll organization;
• ▸PASRAU: on the 10th of the month for certain replacement income;
• ▸Normal actual VAT: deposit and payment between the 15th and 24th of the following month, on the date appearing in the professional area;
• ▸DES and summary statement of customers: around the 11th of the month for intra-community operations;
• ▸payroll tax: monthly due for the taxpayers concerned.

2. Corporate tax deadlines

For companies subject to IS, advance payments are generally:

• ▸March 15, 2026;
• ▸June 15, 2026;
• ▸September 15, 2026;
• ▸December 15, 2026.

The IS balance then depends on the closing date. Management should therefore never be separated from your accounting calendar.

3. Annual and semi-annual deadlines

In 2026, we must also monitor:

• ▸the tax package;
• ▸the CFE/IFER deposit in June for the companies concerned;
• ▸CVAE installments in June and September when the company remains liable;
• ▸VAT or franchise options on certain key dates.

To go further, consult our article on deadline for filing tax returns 2026, our guide on VAT group and our decryption of VAT for SMEs in 2026.

March 2026

The professional tax calendar shows in particular:

• ▸the February DSN;
• ▸monthly VAT for February;
• ▸the first IS installment around March 15.

May 2026

For many companies closing on December 31, 2025, May focuses on:

• ▸the declaration of results;
• ▸remote transmission of the bundle;
• ▸preparation of the IS balance according to the file.

June 2026

June is a heavy month:

• ▸Monthly VAT;
• ▸first CVAE deposit;
• ▸CFE/IFER deposit;
• ▸IS deposit;
• ▸deadlines for certain financial years ending March 31, 2026.

September 2026

The second important block concerns:

• ▸second CVAE deposit;
• ▸IS deposit;
• ▸Monthly VAT;
• ▸intra-community declarations.

Hayot Expertise Advice: the best way to meet the 2026 tax deadlines is to think by flow. A poorly maintained accounting flow always becomes, a few weeks later, a tax or cash flow problem.

Differentiate between tax deadline and production deadline

It is necessary to distinguish:

• ▸the legal date;
• ▸the internal validation date;
• ▸the date of transmission;
• ▸the date of actual payment.

Without this distinction, the manager thinks he is "on time" when the parts are not ready.

Attach each deadline to a manager

A fiscal calendar is only effective if each action has a driver:

• ▸leader ;
• ▸administrative service;
• ▸chartered accountant;
• ▸payroll provider;
• ▸Outsourced DAF.

Integrate cash flow

An unfunded tax deadline creates tensions on:

• ▸VAT;
• ▸IS installments;
• ▸payroll;
• ▸automatic debits.

A tax calendar is only really useful if it is connected to your accounting, your cash flow and your social obligations.

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Thinking that the accountant "necessarily manages everything"

It is still necessary that:

• ▸supporting documents are sent;
• ▸the arbitrations are validated;
• ▸the accounts are reconciled;
• ▸tax options are known in time.

Forget the domino effect

A poorly prepared VAT can delay:

• ▸your bundle;
• ▸your deposits;
• ▸your cash flow visibility;
• ▸your exchanges with the administration.

The 2026 tax deadlines must be managed as a production calendar, not as a simple list of dates. DSN, VAT, IS, bundle, CFE and CVAE must be tracked in a single table, with managers, internal dates and alerts. It is this organization that makes the difference between a peaceful company and a company that is subject to the tax agenda.

📞 Do you want a 2026 tax calendar adapted to your business? Our firm can set up operational monitoring aligned with your accounting and cash flow. Make an appointment with an expert

(Official sources: impots.gouv.fr - Professional tax calendar March 2026, impots.gouv.fr - Professional tax calendar May 2026, impots.gouv.fr - Professional tax calendar June 2026, impots.gouv.fr - Professional tax calendar September 2026, impots.gouv.fr - notice 2571-SD relating to IS deposits)