If the lessor/landlord feels worried, there's no time to spare: when the rent is not paid on time, he should be prompt in issuing a late rent notice by certified mail with acknowledgement of receipt.
If necessary, it is strongly recommended to inform at the same time the surety or the bank granting the surety by sending them a copy of the late rent notice.
If the lessor/landlord receives no answer, and still awaits rent payment, it is about time to start legal proceedings. The landlord can initiate at the same time a legal seizure of the tenant's bank account, or of the tenant's furniture inside the rented premises through a bailiff.
Sample letter of a late rent notice:
You are hereby reminded that you signed a lease contract on... for the rental of the premises located at (enter address), on the third floor right. Under the lease contract, you agreed to pay as rent the sum of... due at the beginning of each month.
Today's date is... and I still have not received the due rent payment. I remind you that according to the article 7 of the French law of 6th July 1989, the lessee is liable for the payment of the rent and recoverable service charges as agreed under the lease contract. Therefore, I am putting you on formal notice to pay without delay the sum of €...
[What follows in the letter depends on whether or not there is a cancellation clause in the lease]
The lease contract includes a cancellation clause:
I remind you that I am entitled to make use of the cancellation clause stipulated in the lease contract, or to deny the lease renewal as non-payment of rent constitutes a legitimate and serious reason for giving notice.
The lease contract does not include a cancellation clause:
I remind you that I am entitled to deny the lease renewal as non-payment of rent constitutes a legitimate and serious reason for giving notice.