SAM80060 - Payments: payments overview: account reconciliation
There are a number of mandatory checks made to ensure all credits and debits directed to SA are allocated or posted to the correct SA customer records.
Once the checks are complete, the information about payments posted in SA is used to determine the pay-over of Class 4 NIC and to reconcile the credits allocated to all Banking systems.
For more information on account reconciliation see the Debt Management & Banking Manual DMBM230000.