Bookkeeping · Foundations · Brief · Intro level
What is a journal entry? Anatomy and proper use
A journal entry is the formal record of one transaction: date, accounts, debits equal to credits, and a memo. Here is each part, when a manual entry is the right tool, and when it is the wrong one.
A journal entry is the atom of double-entry bookkeeping: the formal record of one transaction, showing the date, every account it touches, equal debits and credits, and a memo saying why. Everything else in the ledger — every T-account, every trial balance, every financial statement — is an arrangement of journal entries.
The anatomy, labeled
| Account | Debit | Credit |
|---|---|---|
| Depreciation expense | 250 | |
| Accumulated depreciation | 250 |
Memo: March depreciation on delivery van, 36-month straight line per fixed-asset schedule.
Six parts, each doing a job:
- Date — controls which period the entry affects. A March 31 date and an April 2 date produce different financial statements.
- Debit lines first — the left-side accounts and amounts.
- Credit lines, indented — the right-side accounts. The indent is convention old enough to be universal.
- Balance — total debits must equal total credits, or it is not an entry. Software refuses to save an unbalanced one; paper just quietly ruins your trial balance.
- Memo — the why. "Adjustment" is not a memo. "March depreciation per schedule" is. Six months from now, the memo is the only witness.
- Reference number — the audit trail's handle.
An entry may have many lines — a payroll entry routinely runs eight or more — as long as it balances in total. Entries post from the journal to the general ledger, where each account accumulates its history.
When manual entries are the right tool
Modern software books most entries for you: raise an invoice and it debits receivables and credits revenue behind the scenes. Manual journal entries exist for what no module handles:
Legitimate manual entries and their triggers.
| Situation | Typical entry |
|---|---|
| Monthly depreciation | Debit Depreciation expense, credit Accumulated depreciation |
| Accrue an unbilled expense | Debit the expense, credit Accrued liabilities |
| Spread a prepaid | Debit the expense, credit Prepaid asset |
| Split a loan payment | Debit Loan payable and Interest expense, credit Cash |
| Correct a miscoding | Debit the right account, credit the wrong one |
| Year-end close | Revenue and expenses to Retained earnings |
The loan split and depreciation are the two most owners skip — and the two that most distort a year of statements when skipped.
When they are the wrong tool
The symptom is familiar to anyone who has cleaned up books: the balance sheet shows receivables of 14,000, the customer aging shows 19,500, and the difference is a graveyard of old "fixing AR" journal entries. The fix for a wrong invoice is a credit memo; for a misapplied payment, reapplying the payment; for uncollectible debt, a write-off through the module. Same destination, but the sub-ledger travels with you.
A three-line discipline
- Write the memo before the amounts — if you cannot say why, stop.
- Date the entry in the period it belongs to, not the day you happened to type it.
- Once a period is reconciled and reported, never edit its entries; post a new dated entry instead. Books you can silently rewrite are books nobody can rely on.
Frequently asked questions
- What are the parts of a journal entry?
- Every journal entry has a date, at least one account debited and one credited, amounts where total debits equal total credits, and a memo explaining why. Debits are listed first, credits indented beneath. Many systems add an entry number and the preparer's identity for the audit trail.
- When should a bookkeeper make a manual journal entry?
- Manual entries belong to adjustments the operational modules cannot make: depreciation, accruals and deferrals, prepaid amortization, loan principal-and-interest splits, error corrections, and closing entries. Day-to-day sales, bills, and payments should flow through invoices, bill payments, and the bank feed, which carry customer and vendor detail a bare entry lacks.
- Why shouldn't I fix accounts receivable with a journal entry?
- A journal entry to Accounts receivable changes the account total without touching any specific customer invoice, so the control account stops matching the customer sub-ledger. The receivable looks fixed on the balance sheet while the customer still shows unpaid. Use a credit memo, payment application, or invoice correction instead.