I want to detach bank account for current year, if I do so the transactions of last year remains in the books or will deleted ?

Hello there, Amazon.

When you disconnect or delete an account in QuickBooks Self-Employed (QBSE), all previously categorized transactions and associated data will permanently removed from your books and this can't be undone. On the other hand, hiding an account allows you to retain past transactions (such as those from last year) in your books and reports, but the account will stop downloading new transactions for the current year. 

If you want to preserve historical data from the last year but stop new transactions from coming in for the current year, you can hide the account instead.

Here's how: 

1. Open QuickBooks Self-Employed in a web browser.
2. Select the profile ⚙ icon and then Bank Accounts.
3. Find the account you want to hide.
4. In the Show Account section, select the toggle to OFF.

If you have any questions or other additional concerns with your connected bank accounts let us know. The Community is always here to help.