Once you've applied, filling in a « dossier », you become « allocataire » and receive a « numéro d'allocataire ».
Keep this number, you will be asked to give it everytime you contact your CAF. It's your identification number.
Once you are « allocataire », you can « faire une demande d'aide au logement », « faire une demande d'allocations familiales ». Your CAF will give you these documents, and you'll bring them back to them.
It depends on your personal situation and on how much money you earn. So if you've just arrived in France, you'll have to fill in a « déclaration de ressources ». On this document, you must indicate your wages, the wages of your partner. You will also be asked how many children you have, their age, if they go to school. For the CAF you don't need to be married to be considered a couple.
With this « déclaration de ressources », your CAF will decide if you can receive some money or not. If so, you'll have to
give a RIB and fill a « déclaration de ressources » every year.
If you've been in France for several years you won't need to fill in a "déclaration de ressources".
French administration has decided to make things easier and you will only declare your salaries to the "impôts" (taxes) when you "déclarer vos revenus".
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