What it means
A business with two thousand customers cannot sensibly have two thousand receivable accounts in its general ledger. It keeps them in a sales ledger (the subsidiary ledger), one account per customer, and it keeps one account in the general ledger, the receivables control account, whose balance should always equal the sum of the two thousand.
Every transaction that affects a customer's balance (an invoice, a credit note, a receipt, a discount, a write-off) is posted individually to the customer's account and in total to the control account, from the same source documents. If both postings are correct, the two agree.
The arrangement has three purposes. Practicality: the general ledger and the trial balance deal with one figure for receivables, not thousands.
Control: because the detail and the total are posted separately, usually from the same batch totals but through different routes, an error in one shows up as a disagreement with the other; a reconciliation of the subsidiary ledger to the control account at each period end detects posting errors, omissions and unauthorised entries. Segregation: the person who maintains the sales ledger (dealing with customers, applying cash) is not the person who maintains the general ledger, so a fraudulent adjustment to a customer's account would have to be matched by a corresponding adjustment to the control account by a different person.
The reconciliation is a period-end routine. The subsidiary ledger is totalled (an aged listing of every customer balance); the control account balance is taken from the general ledger; the two are compared; differences are investigated.
Common causes: a transaction posted to the subsidiary ledger and not the control (or vice versa), a transposition error in one posting, a credit note or write-off posted to one and not the other, a journal posted directly to the control account without a corresponding entry in the subsidiary ledger, or a timing difference where a batch was posted to one ledger before the cut-off and the other after. Each is corrected at source.
A reconciliation that balances only after an unexplained adjustment has not achieved its purpose. In integrated accounting software, the subsidiary and control postings are made simultaneously from the same transaction, and disagreement is rare, arising mainly from journals posted directly to the control account (which good systems prevent or flag), from system failures mid-batch, or from data migration.
The reconciliation remains necessary, and auditors test it, because the software's integration is a control that must itself be checked. Control accounts also serve analysis.
The receivables control account, with its opening balance, sales, receipts and closing balance, gives the period's collections in one place; the payables control gives payments; the fixed asset control, with its additions, disposals and depreciation, mirrors the fixed asset register. And control accounts extend beyond ledgers: a payroll control account reconciles gross pay, deductions and net payments; a sales tax control account reconciles tax charged, tax paid and the amount due to the authority; an intercompany control account reconciles balances between group companies.
In practice
Real-world examples.
Example
A retailer's system posts 200,000 sales transactions a month to the receivables control and to individual store and customer accounts, reconciled daily by exception report.
Example
A group's intercompany control accounts in each subsidiary are reconciled to each other monthly, with differences resolved before consolidation.
Example
A payroll control account reconciles the month's gross pay and deductions to the net pay run and the remittances to the tax authority and pension provider.
Think of it
“A control account is a summary total-it should match the sum of all the detailed records underneath.
Formula
Calculation
Receivables Control: Opening balance + Credit sales (from the sales journal) minus Cash received (from the cash receipts journal) minus Credit notes minus Discounts allowed minus Bad debts written off = Closing balance
Reconciliation: Closing control balance = Sum of individual customer balances in the sales ledger
Payables Control: Opening balance + Credit purchases minus Cash paid minus Credit notes received minus Discounts received = Closing balance = Sum of individual supplier balances
Worked example. A wholesaler's receivables control account for June:
- Opening balance: $842,000
- Credit sales for the month (sales journal total): $1,215,000
- Cash received from credit customers (cash receipts journal, receivables column): $1,168,000
- Credit notes issued (returns and pricing corrections): $31,000
- Settlement discounts allowed: $9,500
- Bad debt written off (a customer in liquidation): $14,000
- Closing balance = $842,000 + $1,215,000 minus $1,168,000 minus $31,000 minus $9,500 minus $14,000 = $834,500
Sales ledger listing at 30 June: 1,340 customer accounts totalling $836,900.
Difference: $836,900 minus $834,500 = $2,400 (sales ledger higher). Investigation, correcting each error in the ledger where it occurred:
- A credit note batch total posted to the control account was understated by $1,800 (a keying error in the batch header); the individual credit note had been posted correctly in the sales ledger. Correction: post a further $1,800 credit to the control account, reducing it to $832,700. The sales ledger is now $4,200 higher.
- A cash receipt of $3,200 was applied to a customer's account as $2,600 (a transposition), while the batch total of $3,200 was posted correctly to the control account. Correction: apply the further $600 in the sales ledger, reducing it to $836,300. The sales ledger is now $3,600 higher.
- A customer's invoice for $3,600 was posted twice in the sales ledger (once from the invoice and once from a copy sent for approval) but once in the sales journal, so the control account was right. Correction: remove the duplicate from the sales ledger, reducing it to $832,700. The two ledgers now agree.
The reconciliation is complete with three errors found and corrected: a batch header error that would have overstated revenue in the control account, a transposition that would have left a customer chased for $600 it had paid, and a duplicate invoice that would have had another customer chased for $3,600 it did not owe.
Controls demonstrated: the reconciliation found a batch header error, a transposition and a duplicate posting, none of which would have been visible in either ledger alone. The sales ledger clerk corrected the sales ledger items; the general ledger accountant corrected the control; neither could have adjusted both without the other noticing.
Payables control for the same month: opening $612,000; purchases $884,000; payments $851,000; credit notes received $18,000; discounts received $4,200; closing $622,800, agreed to the purchase ledger listing of 410 suppliers at $622,800 without difference.Case study
Seen in the real world.
A distribution company's receivables control account had disagreed with its sales ledger for eleven months, by an amount that had grown from $4,000 to $61,000. The accountant responsible had posted a monthly "reconciling adjustment" journal to the control account to force agreement, on the basis that the difference was "timing". When she left, her successor reversed the adjustments and investigated.
The difference consisted of three things: customer receipts totalling $28,000 that had been applied in the sales ledger to the wrong customers (leaving some customers chased for paid invoices and others not chased for unpaid ones); credit notes of $19,000 that had been issued to customers from the sales ledger without authorisation and never posted to the control (a sales representative had been issuing credits to favoured customers); and $14,000 of a genuine timing difference and small errors. The unauthorised credit notes were the serious finding: the control account had been doing its job by refusing to agree, and the monthly forced adjustment had switched the alarm off.
The company introduced a rule that no journal may be posted to a control account without the financial controller's approval and a matching subsidiary ledger entry, that the reconciliation be completed item by item within five working days of month end, and that credit notes over $500 require approval outside the sales team. The financial controller's note observed that a control account that is forced to agree is not a control but a decoration.
Watch out
Common mistakes.
- Posting journals directly to a control account to force agreement with the subsidiary ledger, which removes the control and hides the error.
- Reconciling in total and accepting a small difference as timing without listing and clearing the items.
- Allowing the same person to maintain both the subsidiary ledger and the control account, which defeats the segregation the structure provides.
Questions
People also ask.
What is the difference between a control account and a subsidiary ledger?
The subsidiary ledger holds the individual accounts (each customer, each supplier); the control account holds the total in the general ledger. They must agree, and the reconciliation between them is the control.
Why not keep every customer in the general ledger?
Practicality and control: the general ledger stays manageable, the trial balance uses one figure, and the separate posting routes provide a check on each other.
How often should control accounts be reconciled?
At every period end, before the accounts are finalised, and more often (weekly or daily) for high-volume areas such as receivables and cash.
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