More than three months. According to the website of Inquiry Law, if the bank loans overdue exceeds 90 days, that is, more than 3 months, the bank will sue. If the bank sues the court, the borrower should actively fulfill the repayment obligation after the people's court makes a judgment. If it refuses to perform, the bank can apply to the court for enforcement, and the court will seal up and detain the borrower's property during this period.