How do you reconcile the sales ledger to the sales ledger control account?

Total all individual customer balances in the sales ledger (a list of balances) and compare to the sales ledger control account balance in the nominal ledger. Investigate differences—posting errors, omitted entries, casting errors, or a transaction in one but not the other—and correct them so the list agrees with the control account.

List of debtors balances total: 6,500
SLCA balance: 6,650
Difference 150 -> find and correct (e.g., an omitted credit note).