The reason why the Bank of China credit card application numbers are different in each branch is to distinguish and manage different application information. This numbering system can help banks accurately record and query the credit card application status of each branch, including information such as approval progress, related documents and materials. At the same time, this also allows each branch to process and approve credit card applications independently, improving work efficiency and ensuring data accuracy. This approach is for better division of labor and management, and helps ensure the transparency and fairness of the application process. Numbering differences between branches are part of the design of the bank's internal regulations and processes. Therefore, the application number for Bank of China credit card is different in each branch.