When it is considered that you have received income from individual activity?

Income from individual activity is considered to have been received when you receive money (cash accounting principle). But if you are a VAT payer or have declared to the STI that you are using non-current assets (have submitted a Form FR0457), then it is considered that you have received income after you have provided the service / or sold the goods (accrual accounting principle). The accrual accounting principle shall start to be applied in a tax period in which you are registered as a taxpayer for VAT purposes or attribute assets to individual activity (submit the Form FR0457). After having started applying the accrual accounting principle, you have to apply it until the end of the activity. 

From 2023-01-01, if you are not obliged to apply the accrual accounting principle (i.e. you are not registered as a VAT payer or you have not assigned a fixed asset to your individual activity), you can choose which (cash or accrual) accounting principle to apply.