When are social security contributions paid in France?

Question

I need to register for French social security (CMU de base) for the first time. I don't fall under the employer, self-employed or student schemes. I do have income, though, so it will cost me and the cost is significant). As I understand, I can register with CPAM at any time during the year, but what period does my initial payment cover? In other words, when would I have to make the next year's contribution?

This is probably a non-issue for most people in France, since they're covered continuously and simply pay once a year, so when the each year's cover "ends" is a purely academic question. However, it is an issue for me when registering for the first time. Basically, I want to avoid the situation where I pay a full year's contribution for only a month or two of cover.

Answer 1

The way I understand the page about this on service-public.fr:

• By default, you have to pay each quarter but you can also ask to pay monthly.
• The first payment is due on the date you start being covered.
• How much you should pay, in total, is based on the duration of insurance cover (“au prorata de la durée d'affiliation”), you don't have to pay for a full year for a few months.