A subsidiary ledger is the detailed record behind a single general ledger account, carrying one row for each individual account or item inside that balance, one per customer, vendor, asset or job. The general ledger account it supports is the control account, and the subsidiary ledger’s total has to agree with the control account balance. Subledger is the same record under a shorter name.
The Internal Revenue Manual states the relationship in one line, defining subsidiary accounts as accounts that provide necessary details in support of certain general ledger accounts (Internal Revenue Manual 3.17.64.1.6, Terms/Definitions). The auditing standards put them inside the records an audit works from, defining accounting records to include the general and subsidiary ledgers (AICPA Professional Standards, AU-C Glossary of Terms).
How a Control Account and Its Subsidiary Ledger Fit Together
The same amounts reach both records under the debit and credit rules that govern every other entry, set out in bookkeeping and debit vs credit. The individual detail lands on a subsidiary ledger row and the control account carries the same amount in summary, which is why the general ledger shows one balance and the subsidiary ledger shows its composition. A month of receivables closes like this:
General ledger
Accounts receivable, control account 61,500
Accounts receivable subsidiary ledger
Customer A, invoices 1042 and 1058 28,000
Customer B, invoice 1061 16,500
Customer C, invoice 1049 12,000
Customer D, invoice 1066 5,000
Total 61,500Proving those two totals agree is what the Internal Revenue Manual calls reconciliation, the act of ensuring that the total of the monetary balance of the appropriate general ledger account agrees with the balance in the related subsidiary account, with all variances identified (Internal Revenue Manual 3.17.64.1.6, Terms/Definitions).
The Subsidiary Ledgers on a Client’s Books
Receivables and payables are the two that almost every client’s books carry: the open invoice detail behind accounts receivable, and the open supplier detail behind accounts payable.
The fixed asset ledger is the next one a preparer meets, one row per asset carrying its cost, the date it was placed in service and the depreciation taken against it, standing behind fixed assets and accumulated depreciation. Payroll keeps one row per employee and inventory one row per item. Job costing applies the structure to work rather than to parties, one row per job, which is how contractor books are built and is worked through in construction bookkeeping.
What a Tie to the Control Account Proves
A tie proves the detail adds up to the summary, and that is the whole of what it proves. Its absence is treated as a warning sign: the auditing standards give accounts receivable subsidiary ledgers not reconciled to the general ledger account in a timely or accurate manner as an example of a circumstance that may be a deficiency, a significant deficiency or a material weakness (AICPA Professional Standards, AU-C section 265, appendix).
What a total cannot see is which row an amount sits on. Post one of those invoices against the wrong customer and the subledger total does not move, so the tie holds while the detail underneath it is wrong. Balancing a subsidiary account is therefore an item level act as well, comparing the document behind a transaction against the journal posting, with the money amount and the accounts debited and credited both matching the document (Internal Revenue Manual 3.17.64.2.3.1, Subsidiary Records and Balancing). Following one row back to its source document is the audit trail.
What a Subsidiary Ledger Is Not
It is not a trial balance. A trial balance lists the general ledger accounts with their balances in two columns, which is worked through in trial balance, and a subsidiary ledger sits behind one of the accounts on that list, so its rows never appear on it.
Common Questions
One row for each individual account or item behind the control account, carrying that party’s transactions and its running balance. The rows hold the identifiers a summary drops, the invoice number, the date and the party or job the amount belongs to.
The general ledger carries one balance for every account the business uses. A subsidiary ledger carries the composition of one of those balances, so it is not an account in its own right and it never adds anything to the ledger’s total, because its whole amount is already sitting in the control account.
GL and SL are the everyday abbreviations for general ledger and subsidiary ledger. The GL account is the total, the SL is the detail that has to add up to it, and the letters change nothing about either record.
Accountably places trained offshore accountants inside US CPA and EA firms, and a firm can put a block of its own bookkeeping through a trial task and have its own reviewer check the subledger ties that come back.
