According to ICANN regulations, the previous domain registrar has five days to release the name to the Gaining (new) Registrar after receiving transfer verification (EPP Code) from the registrant or administrative contact for the domain(s).
The transfer will be completed automatically after the five (5) day waiting period.
NOTE: The five-day waiting period begins once the Registrar of Record has been notified of the transfer request by the registry. This typically occurs within 12-24 hours after the transfer has been approved by you or your client.