Legal analysis: there is no clear time limit for how long to sue the bank after door-to-door collection. However, if it is overdue for more than 3 months and has not been repaid after two effective collections by the bank, if the amount owed exceeds 1,000, the bank will sue within one week after the completion of the door-to-door evidence collection.

Legal basis: Measures for the Supervision and Administration of Credit Card Business of Commercial Banks

Article 1 In order to standardize the credit card business of commercial banks, protect the legitimate rights and interests of customers and banks, and promote the healthy and orderly development of credit card business, these Measures are formulated in accordance with the Banking Supervision Law of the People's Republic of China, the Commercial Bank Law of People's Republic of China (PRC), the Regulations on the Administration of Foreign Banks in People's Republic of China (PRC) and other laws and regulations.

Article 2 Commercial banks shall strictly abide by national laws, regulations, rules and relevant policies, and follow the principles of equality, voluntariness, honesty and credibility.