Most Zipcar application requests are approved instantly allowing customers to book their first trip on the spot. However, some new Zipcar accounts may take a while longer to verify all their personal information is in check. In this case, approval may take between three to five business days. If you would like to get a detailed answer on how your account's approval process is going then don't hesitate to get in touch with Zipcar's customer service team which can answer all your questions.