Deposit in Caisse centrale du crédit mutuel, 2.25% for 10 years

This automated surplus cash investment service allows you to schedule a monthly transfer from your bank account to your LDDS. Subscription conditions:

Opening an LDDS is intended for individuals, taxpayers residing in France for tax purposes, spouses, or partners linked by a civil solidarity pact (PACS) to the taxpayer subject to joint taxation, who do not yet have an LDDS.

You can find more detailed information on the bank's website.