1. Decline in credit score: Overdue for less than 9 days will have a negative impact on personal credit score, which may decline. Credit score is an important indicator to evaluate personal credit status, and banks and other financial institutions will evaluate personal repayment ability and credit risk according to credit score.

2. Penalty interest and late payment: Credit card bills overdue for less than 9 days may incur penalty interest and late payment. Banks usually calculate the amount of penalty interest and late fees according to the number of days overdue and the amount overdue, and these extra expenses will increase the repayment burden of individuals.

3. Impact on credit history: overdue for no more than 9 days will also have an impact on personal credit history. Credit record is a file that records an individual's repayment history and credit behavior, and it will be referenced by institutions when applying for credit products such as loans and credit cards in the future. Overdue records will leave traces in the credit records, which may adversely affect the individual's future credit application.

to sum up, a credit card overdue for less than 9 days will have a negative impact on personal credit, including a decline in credit score, penalty interest and late fees, and an impact on credit records. Therefore, timely repayment is an important step to maintain a good credit status.

Extended information:

Overdue for no more than 9 days means that the credit card bill is delayed for no more than 9 days after the repayment date. Overdue for more than 9 days will be considered as serious overdue and may face more serious consequences, such as bank debt recovery and legal proceedings. Therefore, it is very important to pay off the debt as soon as possible after the credit card bill is overdue. In addition, each bank may have different ways to deal with overdue, and the specific situation may vary from bank to bank.