The bank loan is still valid if it is not collected for 20 years, but the account is estimated to have been "cancelled" by the bank. Such loans are "irrecoverable" and will be written off in the bank's profits. Moreover, the bank will hang up the account and will not collect the borrower again, but it will affect the credit information and leave a record of non-performing loans.
It is somewhat inappropriate to use the word "invalid" to describe the loan 20 years ago. In the professional vocabulary of banks, it is called "bad debts". Whether it is a bank 20 years ago or a bank 20 years later, every account of the bank is recorded. The reason why banks don't accept loans 20 years ago is because banks classify loans as "bad debts" at the time of settlement and then write them off.
The so-called "loan write-off" refers to the non-performing loans that the bank is still unable to recover after many efforts, and this loan will be "written off" in the bank's profits. This means that bank loans "don't have to be repaid".
Although there is no need to repay the bank loan, there are still records. China's bank credit information system was launched in 2006, 20 years earlier than this year. At that time, manual bookkeeping was used. Later, after computer bookkeeping was enabled, all the previous manual bills were entered into computer records.
Because the loan has been "written off" and only entered into a record of the bank, the borrower will be listed as a "non-performing loan" in the credit record. Unless the loan is repaid, this record will disappear in five years, otherwise it will always exist. Therefore, the loan 20 years ago is still valid and will exist in the personal credit record, but the bank may not collect it again.