The classification of your non-trading profits (NTC) as professional or non-professional represents a major financial challenge: this distinction can save you more than 20 points in social security contributions. In concrete terms, non-professional BNC are subject to only 17.2% social security contributions, compared with 40% to 45% for professional BNC. On €10,000 of income, you pay only €1,720 instead of €4,000 to €4,500. Non-professional BNC refers to ancillary or patrimonial income: occasional furnished rentals, royalties received on an ancillary basis, or self-employed activities carried out on a non-regular basis. Understanding these mechanisms will enable you to significantly optimize your tax and social security situation.

What are BNC Non Professionnels?

Non-professional non-commercial profits (BNC) refer to income derived from an activity carried out on an ancillary basis or from the management of assets, such as occasional royalties or income from non-routine furnished rentals. This classification is based on three criteria: the absence of registration with a compulsory social security scheme in respect of this activity, the ancillary nature of the income, and the absence of direct and continuous personal involvement. Unlike professional BNC, this income is exempt from social security contributions for self-employed workers and from affiliation to the Sécurité sociale des indépendants (SSI), but remains subject to social security deductions at the overall rate of 17.2%, which represents a significant financial advantage when determining the applicable social security contributions regime.

Criteria for distinguishing between professional and non-professional BNCs

For an activity to qualify as professional, three cumulative criteria must be met: personal, direct and continuous participation in the activity, registration with a compulsory social security scheme, and receipts representing more than 50% of the professional income of the tax household. As soon as a single criterion is missing, the activity is classified as non-professional BNC. This distinction directly determines the level of social security contributions: BNC non-professionals are subject only to 17.2% social security contributions, while the switch to professional status entails social security contributions of between 40% and 45% of net income.

Social security contributions for non-professional BNCs

Non-professional NCBs are exempt from the social security contributions for self-employed workers managed by URSSAF. No affiliation to the SSI is required for this income. The financial advantage is considerable: on €20,000 of non-professional NBI, you pay €3,440 in social security deductions, compared with €8,000 to €9,000 in contributions if the same income came under the professional system. This difference represents a saving of over 50% on social security contributions.

On the other hand, this income remains subject to social security contributions at the overall rate of 17.2%. This contribution is broken down into three components: the CSG at 9.2%, the CRDS at 0.5%, and the solidarity levy at 7.5%. On a net income of €20,000 in non-professional BNC, this represents €1,840 in CSG, €100 in CRDS, and €1,500 in solidarity levy. These levies apply to the net amount of BNC, after deduction of actual deductible expenses or application of the flat-rate allowance. The tax authorities deduct these amounts directly from your income tax bill, without you having to take any specific steps with URSSAF.

Calculation and Payment Terms

Social security contributions are calculated automatically on your net income. For example: for €30,000 in micro-BNC income, the 34%flat-rate allowance reduces the tax base to €19,800, generating €3,408 in social security contributions (17.2%). Under the controlled declaration system, your actual expenses are deducted before application of the 17.2% rate.

Payment is automatically integrated with your income tax via deduction at source or by instalments. Unlike BNC professionals, you don’t have to deal with URSSAF: the tax authorities calculate and deduct the contributions due directly from your tax notice.

Non-professional BNC tax return

You must declare your non-professional BNC on your annual tax return (form 2042). The micro-BNC regime applies automatically if your income does not exceed the tax threshold of 77,700 euros (2024), with a flat-rate deduction of 34% used to calculate the 17.2% social security deductions. Above this threshold, you are subject to the controlled declaration system (form 2035), where social security contributions are applied to your net income after deduction of actual expenses.

Declaration optimization

To reduce the base for the 17.2% social security levy, you can opt for the controlled declaration system if your professional expenses exceed 34% of your income. This option allows you to deduct your actual expenses rather than the flat-rate allowance, thereby reducing the basis for calculating social security contributions. The option must be exercised before February 1st of the tax year, and remains valid for two years, allowing optimal taxation of your non-professional BNC.

Combining Non-Professional BNC with Other Income

You can combine non-professional NCBs with other sources of income (salaries, pensions, professional NCBs, property income) without generating additional social contributions to the self-employed scheme. This income is subject only to the compulsory 17.2% withholding tax, and is added to your overall income when calculatingdirect taxation. Non-professional NCBs do not give rise to any social security entitlements: they do not generate pension quarters, health insurance entitlements or daily allowances.

Social and patrimonial consequences

The non-professional BNC system generates substantial savings in social security contributions: you pay only 17.2% in social security deductions, compared with 40% to 45% in contributions for self-employed workers, representing a saving of 22 to 28 points. However, this immediate financial advantage is accompanied by major drawbacks: this income generates no pension entitlement (0 validated quarters), no health and maternity cover, and no family allowances in respect of this activity. From a financial point of view, non-professional NBI is included in the calculation of your reference tax income (RFR), which determines your eligibility for certain social benefits and tax exemptions.

Evolution towards a Professional Status

When your activity reaches the threshold of 50% of your professional income, and you meet the criteria of direct participation and compulsory social security registration, you automatically switch to professional BNC status. This change in status has a direct impact on your social security contributions: you go from paying 17.2% social security contributions to paying 40-45% SSI contributions calculated on your net taxable profit. In concrete terms, on €50,000 of net income, you pay €8,600 in non-professional status, compared with €20,000 to €22,500 in professional status. In return, you validate pension quarters and benefit from full social security coverage. It’s crucial to declare this change quickly to avoid any tax or social security adjustments.

Anticipating the transition to professional status

As soon as your activity meets the criteria for professional status, you must register with URSSAF. Failure to do so may result in adjustments and penalties. You need to be particularly vigilant to anticipate this changeover and avoid any adjustments.

Optimize Your Tax and Social Situation

Non-professional NICs benefit from an advantageous social security system, with social security contributions limited to 17.2%, compared with 40% to 45% for professional status. However, this substantial saving is accompanied by a total absence of social rights: no validation of pension quarters, and no health and maternity coverage. You need to keep a close eye on the €77,700 annual income threshold that determines application of the micro-BNC system, with its 34% flat-rate allowance, as well as on the criteria for switching to professional status, which would radically alter your social security contributions.