Income tax - How are exceptional income taxed?

Income is considered exceptional if it exceeds your usual income and do not renew each year.

For example, the following revenues:

• Reimbursement of a redemption of retirement quarters (for years of study or incomplete years)
• Additional bonus received by an employee for exceptional services
• Allowance of door-step received by an owner
• One-time lump sum payment replacing a small pension
• Compensatory allowances of notice or paid leave (e.g. in case of dismissal).

To be considered exceptional, an income must exceed the average taxable income of the previous 3 years.

The comparison applies to the revenues of the tax shelter.

However, some income is considered to be exceptional whatever their amount.

This is particularly the case for the following types of income:

If you received an exceptional income in 2024, you can request that it be taxed on the quotient system.

The quotient system avoids the progressivity of the .

It applies in 2 steps:

1. Add quarter from one-time income to your regular income
2. Multiply by 4 the corresponding additional tax.

The tax on exceptional income is paid in one go.

The income to be taxed under the quotient system shall not not included in other reported income.

You must enter the total of these revenues as one of the following:

• Within the framework provided for on page 3 of declaration No 2042 C (line 0XX)
• On free paper attached to Declaration No 2042.

You must detail the amount and nature of income exceptional to be imposed on the quotient, received by each member of the household.

Tax returns via Internet is required if your principal residence is equipped with internet access and you are able to file your return online.

The 2025 income tax return for 2024 is complete.

The 2026 tax return for 2025 will begin in April 2026.