Article 1178 of the Civil Code stipulates that the nullity of a contract has a retroactive effect, meaning that the contract is deemed never to have existed. Each party must then return what they have received, in accordance with Articles 1352 et seq. This provision is fundamental for understanding the legal implications of nullity.

Under Article L. 222-7 of the Consumer Code, the consumer has 14 full calendar days to exercise their right of withdrawal without having to justify their decision. This period begins from the date of conclusion of the contract or, if later, from the date of receipt of the contractual terms and mandatory pre-contractual information.

Under Article L. 222-13, if the consumer has expressly requested the commencement of the service before the expiration of the withdrawal period, they may be required to pay for the proportionate amount of service provided, provided that the amount due was communicated to them in advance. However, in the absence of an express request or prior information, no amount may be claimed.

In the event of a late refund after a withdrawal, progressive surcharges apply under Article L. 222-13: 5% between the tenth and twentieth day, 10% between the twentieth and thirtieth day, then five additional percentage points per month of delay. These surcharges aim to protect consumer rights in the event of non-compliance with deadlines by the provider.

Under Article L. 222-9 of the Consumer Code, financial instruments, including shares and bonds, are excluded from the right of withdrawal due to their significant interest for market professionals. This exclusion aims to prevent the exploitation of market fluctuations during the withdrawal period.

Under Article L. 222-13, even if the consumer has requested the performance of the service before the expiration of the withdrawal period, they only need to pay the proportionate part already provided, if the amount was communicated in advance. The consumer is never required to make full payment in the event of withdrawal.

Article L. 222-13 stipulates that the provider must process the refund within a maximum of 30 days following the notification of withdrawal. Beyond this period, progressive surcharges apply: 5% between the tenth and twentieth day, 10% between the twentieth and thirtieth, etc.

Contracts excluded from the right of withdrawal include financial instruments (shares, bonds), order reception-transmission services, and crypto-assets since late 2024. The conditions for applying charges after withdrawal require an express request from the consumer and prior information on the amount due. This distinction is essential for correctly applying the rules.