In open invoice systems, such as this, each invoice is billed and paid individually. Cash
from customers may be received and processed as just described or may be sent directly
to a bank lock-box. In either case, the remittance advices (and credit memos to reflect
returns and allowances) are sent to the AR department where the clerk enters them
into the system via a terminal. Each remittance record is assigned a unique remittance
number and is added to the remittance file. Placing the remittance number and
the current date in the respective fields then closes the corresponding open invoice
record.