To pay your salary/subsistence and other indemnities (where applicable), CERN requires you to register the details of your Swiss bank account.
This must be done through an EDH form before the third week of the month of your arrival (cca. 20-21st of the month). This applies also for those who already had a contract with CERN and where there is a gap between contracts.
If you do not have a Swiss bank account, you may choose to open or use an account with a bank located on the CERN site or with another bank established in Switzerland, or even with a French bank in the region that offers its customers Swiss franc accounts (i.e. with an IBAN starting with CH), such as Crédit Mutuel, CIC, Crédit Agricole etc.
More information is available on the admin e-guide.
If you cannot complete the EDH form in time, the payment will be postponed, until you have completed the form. One this is done, payment may take 4 or 5 working days.