Importing function will skip individual transactions only if there is already one with the same clear date and amount.
So if your MT940 file contains bank transaction on 13/04/2019 for 20 EUR and your accounting file doesn’t contain transaction with this clear date and amount, then this bank transaction will be imported.
Just keep in mind, bank transactions have two dates.
- Date (which is date for accounting purposes)
- Clear date (which is date for bank reconciliation purposes)
If clear date is not entered, then clear date will be the same as “date” (this is the case for almost all bank transactions - clear date is different from transaction date only if entering cheques, pending deposits etc.)