CNSS quarterly declaration: deadlines, online filing and mistakes to avoid

Short answer: You file the quarterly salary declaration with the CNSS (National Social Security Fund) and pay the contributions no later than the end of the first fortnight after the quarter: January 15, April 15, July 15 and October 15. Each month of delay, even a partial month, costs 1% of the unpaid contributions, plus another 0.5% if you have not declared the salaries.

Every quarter, the same story plays out: payroll closes late, the accountant opens the platform on the evening of the 14th, the electronic certificate has expired, and the declaration goes out on the 17th. October 2026 adds a complication: the third-quarter deadline, October 15, fell on a public holiday.

Key points

• Deadlines: January 15, April 15, July 15 and October 15 (Article 105 of Law No. 60-30); payment goes with the declaration.
• Rates: 17.07% for the employer and 9.68% for the employee, for a total of 26.75%, since January 1, 2025.
• Penalties: 1% per month or fraction of a month on unpaid contributions, plus 0.5% if you have not declared the salaries by the deadline.
• October 15, 2026: public holiday; as of October 9, 2026, we have not seen any CNSS notice about a postponement.
• Next deadline: January 15, 2027, for the fourth quarter of 2026.

What is the deadline for the CNSS quarterly declaration?

The deadline falls at the end of the first fortnight after the quarter. Article 105 of Law No. 60-30 of December 14, 1960, as amended by Law No. 2007-51 of July 23, 2007, requires the employer to submit its salary declaration within this period and to enclose payment of the contributions.

The declaration is nominative: it lists every employee for the quarter. Our article on 2026 CNSS rates and the full cost of an employee details how to calculate contributions.

October 15, 2026 was a public holiday: what should you do if you have not filed yet?

File and pay without waiting for confirmation of a postponement. October 15, 2026, Evacuation Day, is a public holiday. The DGI (tax administration) moves its own deadlines to the next business day: in October 2025, it set the 16th instead of the 15th. For the CNSS, we have not seen any 2026 notice: a postponement to October 16 remains an inference, not a confirmed rule. If the CNSS kept the 15th, filing and paying on the 16th counts as a partial month of delay: 1% of contributions, plus 0.5% for the late declaration.

Keep proof of filing and payment, then ask your regional office which date the CNSS applied.

How do you file salaries and pay contributions online?

You use the “online salary declaration and contribution e-payment” service, available from cnss.tn and the services.cnss.tn/dspc platform. The steps follow a guide by a chartered accountant, published by Managers in September 2025.

1. Enroll with a TunTrust electronic certificate; the one you use for online tax filing remains valid. You create a user, add the company, select the “online declaration” and “e-payment” profiles, then wait for validation (up to 24 hours).
2. Enter the declaration in the online form, or import a compliant text file.
3. Sign the declaration electronically, then the summary statement: payment depends on this step.
4. Pay by electronic bank debit, from up to three accounts, or at the regional office by bank transfer or check.

Two caveats. None of the sources consulted publishes the specifications of the import file: request them from the CNSS before you build an export. And nothing allows us to state that online filing is mandatory for all companies.

How much does a late declaration or payment cost at the CNSS?

A delay costs 1% of contributions per month, and 1.5% if the declaration is missing too. Article 105 of Law No. 60-30 provides for two penalties:

• 1% per month of delay or fraction of a month on contributions not paid by the deadline;
• an additional 0.5%, calculated on the contributions due, per month of delay or fraction of a month, when the employer has not declared the salaries by the deadline.

Example: your gross payroll for the quarter reaches 60,000 TND. Contributions amount to 60,000 × 26.75% = 16,050 TND. You declare on time but pay ten days late: the fraction of a month counts as a full month, so 16,050 × 1% = 160.500 TND. You neither declared nor paid: 16,050 × 1.5% = 240.750 TND per month or part of a month, so 722.250 TND after three months.

The CNSS then sends a formal notice by registered letter. Without regularization within 15 days, it issues an ex officio assessment and recovers the debt through an enforceable statement of liquidation (Articles 104 and 105).

Which errors distort the declaration or delay filing?

Errors come less from the calculation than from the organization. Five come up often:

• Filing on the last day. The platform gets overloaded near the deadline: the CNSS extended online filing for the fourth quarter of 2024 to January 17, 2025, in response to the surge of online declarations.
• An expired TunTrust certificate. Without it, you can sign neither the declaration nor the summary statement.
• Outdated rates. Some Excel files still apply 9.18% to the employee instead of 9.68%.
• Missing or misidentified employees. Fixed-term contracts, seasonal workers, a wrong registration number or national ID card (CIN) number: a nominative declaration does not tolerate an incomplete record.
• Gaps between payroll and the declaration. Bonuses, benefits in kind and back pay get treated differently from one entry to the next. Back pay paid in the fourth quarter belongs in the January 15, 2027 declaration.

What routine helps you file on time every quarter?

Aim to file before the 10th of the month, not the 15th, in five steps:

1. As soon as you hire: complete the employee record (identity, CIN, registration number) and declare the employee right away.
2. Every month: close payroll from a single data source, with a dated rate table. If your payslips come out of a spreadsheet, see how to move from Excel to an ERP.
3. At D-10: check the TunTrust certificate, then reconcile gross payroll with the CNSS base, and the paid headcount with the nominative list.
4. Before the 10th: file, sign and pay; archive the declaration, the summary statement and the proof of payment.
5. At D-3: an alert serves as a safety net.

Also plan the cash for social charges. If a debt already exists, ask your regional office for a payment schedule.

How AISYSNEXT supports you

AISYSNEXT starts from your actual payroll process and works alongside your chartered accountant, without replacing them.

• We audit your workflow, from hiring to filing: data entry, spreadsheets, checks, calendar.
• We configure AROVA ERP to bring personnel files, leave, attendance and payroll items together in a single source, with a dashboard of your deadlines.
• We study with you how to connect your management system to CNSS online filing, and we develop the matching export on a quote basis, once the format has been obtained from the CNSS.
• We migrate your data, train your team and provide support from Tunis.

Describe your organization in a free quote request or contact our team.

Frequently asked questions

Do you have to declare salaries even if the company cannot pay by the deadline?

Yes: the obligation to declare remains, and you avoid the additional 0.5% monthly penalty. A declaration without payment still exposes you to a formal notice: ask your regional office for a payment schedule.

Can the CNSS cancel late-payment penalties?

Only within narrow limits. Article 107 of Law No. 60-30 restricts the waiver of penalties to grounds of general interest, under the procedure of Decree No. 96-342 of March 6, 1996. The last known social security amnesty ended on April 4, 2025, and we found no trace of any new amnesty in 2026.

Can an employee check what the employer has declared?

Yes. Since late August 2026, the national mobile app “Khadamet” has given citizens access to their career information and their CNSS declarations. A missing quarter therefore also shows up on the employee’s side.

Sources

• CNAM — nominative quarterly declaration of workers
• Jurisite Tunisie — Law No. 60-30, Articles 104 to 107
• PwC Tax Summaries — social security contribution rates
• Diwan — deadline calendar
• La Presse — extension of the CNSS filing deadline, January 16, 2025
• Managers — guide to CNSS online filing, September 10, 2025
• allAfrica / La Presse — end of the social security amnesty, April 4, 2025
• Entreprises Magazine — Khadamet app, September 1, 2026

Article up to date as of October 9, 2026. It provides information and does not replace the advice of your chartered accountant or legal counsel.