What are the main accounting mistakes to avoid in Luxembourg?

The 7 most frequent mistakes are: confusing output and input VAT, missing the accounts filing deadline, mixing personal and business expenses, forgetting depreciation, mismanaging expense reports, ignoring CCSS obligations, and underestimating corporate income tax.

What is the penalty for late filing of accounts in Luxembourg?

Failure to file annual accounts within 7 months of year-end exposes the company to penalties of up to €5,000 per offence with the Trade and Companies Register (RCS).

How can I avoid mixing personal and business expenses?

The best practice is to open a dedicated business bank account as soon as the company is set up and never use this account for personal expenses. Any business expense paid personally should be processed through a reimbursed expense report.

What is the aggregate corporate tax rate in Luxembourg City?

In Luxembourg City, the aggregate corporate tax rate (corporate income tax + municipal business tax + employment fund contribution) is around 24.94%. It breaks down as: corporate income tax 17%, municipal business tax 6.75%, and employment fund contribution 1.19% (on corporate income tax).

Can accounting errors from past financial years be corrected?

Yes, errors from prior financial years can be corrected. Depending on their nature and significance, they are recognised as exceptional expenses or income in the current year, or through a restatement of equity if they are material and recurring. A chartered accountant can help you identify and regularise these situations.

The 7 Most Common Accounting Errors in Luxembourg

Despite a standardized accounting framework, keeping the books of a Luxembourg company remains a source of recurring errors that cost dearly: administrative fines, tax reassessments, refused bank credit, tension with shareholders. After auditing hundreds of SME files in Luxembourg, here are the 10 most common accounting errors and how to avoid them in 2026.

1. Confusing shareholder current account and cash

A very common error in family SARLs: the director draws money from the company's bank account without distinguishing salary, dividend, expense reimbursement or advance. These untraceable movements create a debit shareholder current account, which is tax-reclassified as remuneration (and subject to social contributions) or as a hidden dividend (+ withholding tax). Solution: a dedicated journal, supporting documents for each drawing, and a written policy approved in the general meeting.

2. Neglecting monthly bank reconciliation

Without reconciliation, uncashed cheques, forgotten transfers and unrecorded bank fees pile up. At year-end, discrepancies of several thousand euros sometimes going back 10 months. Solution: systematic monthly reconciliation, ideally automated via software connected to the banking feed (PSD2 open banking).

3. Misapplying intra-EU VAT

Intra-EU VAT is complex: B2B services (reverse charge by the client), B2C services (VAT of the provider's country), goods sales (OSS rules since 2021 for e-commerce). Classic errors: forgetting the "reverse charge" mention on the invoice, VAT charged to an EU customer with a valid VIES number, forgotten INTRASTAT return. Solution: systematically check VIES via the official portal, qualify each transaction before invoicing.

4. Late filing of annual accounts with the RCS

Accounts must be filed with the RCS via eCDF within 7 months of year-end. A delay exposes you to administrative fines (from €500 to €25,000 for large companies), judicial dissolution in case of recurrence, and loss of banking credibility. Solution: plan from October for a 31 December year-end, with entry review in November.

5. Forgetting provisions for risks and charges

A commercial dispute, an ongoing warranty, a potential tax reassessment must be provisioned as soon as the triggering event is probable and quantifiable. Omitting them distorts the result, the balance sheet and can be reclassified as accounting manipulation. Solution: systematic annual risk review by the director and the accountant, documentation of the assumptions.

6. Failing to record depreciation

Fixed assets (equipment, vehicles, software, fit-outs) must be depreciated over their useful life according to a plan defined at acquisition. The absence of depreciation artificially inflates the taxable result and equity. Solution: depreciation schedule kept up to date, checked at each closing.

7. Not tracking the legal reserve

Every SARL and SA must allocate 5% of annual net profit to the legal reserve until it reaches 10% of the share capital. For the SARL-S, it's 25% up to €12,000. Omitting this can void dividend distributions and trigger the managers' liability. Solution: automatic calculation as soon as the result is validated by the general meeting.

8. Ignoring RBE obligations

The Register of Beneficial Owners (RBE) must be kept up to date. Penalties: fine up to €1.25M for failure to declare, possible prison sentence in aggravated cases. Solution: update as soon as an ownership threshold changes, systematic annual check.

9. Confusing gratuity and bonus

In Luxembourg, the year-end gratuity (13th month) is due pro rata on departure for employees with at least 12 months of service. Its accounting treatment (provision vs payment) has a direct impact on the result. A bonus is discretionary and can qualify for a favorable tax regime (profit-sharing bonus regime). Solution: clear clause in the contract, accounting distinction from payroll preparation.

10. Not preparing the year-end closing in advance

Waiting until January to start closing the 31 December accounts guarantees stress, omissions and often late filing. Solution: closing plan from October (inventory, confirmation letters, review of customer and supplier accounts, provisions, cut-off), with a pre-close at 30 November that anticipates 80% of the adjustments.

Going further

Bookkeeping basics: Tenue de la comptabilité au Luxembourg : Obligations et bonnes pratiques.
Detailed Standard Chart of Accounts: plan-comptable-normalise-luxembourg.
Preparing your annual accounts: comptes-annuels-luxembourg-guide.

Preventive accounting audit Bookkeeper.lu offers an accounting health check: review of the last 12 months, risk identification, prioritized recommendations.