What it means
Accounting rests on double entry, the principle that every transaction affects at least two accounts. A journal entry is how that principle is written down: a date, the accounts touched, the debit amounts, the credit amounts and a short description.
The debits must equal the credits, which gives the system a built-in arithmetic check. Debit and credit are not the same as good and bad.
Debits increase assets and expenses and reduce liabilities, equity and revenue, while credits do the opposite. Once you accept that convention, reading an entry becomes mechanical rather than mysterious.
Most entries are now created automatically. Raising an invoice, paying a supplier or running payroll generates entries in the background without anyone typing them.
What finance teams actually write by hand are manual entries: accruals, prepayments, depreciation, corrections and reclassifications at period end. That is why manual entries attract attention from auditors and controllers.
A manual entry can move profit between periods or between departments, so most organisations require a preparer, a reviewer and supporting documentation for each one. Large or unusual entries posted late in a closing period are a standard audit test.
Entries flow from the journal into the general ledger, where they are grouped by account and totalled into the trial balance and then the financial statements. If a number in a report looks wrong, the trail runs backwards from statement to ledger account to individual entry to the original invoice or contract.
Being able to follow that chain is what makes a set of accounts auditable.
In practice
Real-world examples.
Example
A retailer's controller finds that $22,000 of December marketing spend was coded to January. She posts a reclassification entry debiting December marketing expense and crediting January marketing expense, with the supplier invoice attached as support.
Example
A consultancy finishes $65,000 of work in June but will not invoice until July. At month end it posts an accrual debiting accrued revenue and crediting revenue, so June's profit reflects the work actually performed. The entry is reversed in July when the invoice is raised.
Example
A manufacturer pays $60,000 in advance for a twelve-month insurance policy. The initial entry debits prepaid insurance and credits cash, and each month a further entry moves $5,000 from prepaid insurance to insurance expense.
Think of it
“A journal entry is like a diary entry for your business finances. It records what happened, when it happened, and which accounts were affected.
Formula
Calculation
Formula: total debits = total credits, for every entry without exception. In words: debits increase assets and expenses, credits increase liabilities, equity and revenue, and the two columns must balance before the entry can be posted.
Worked example. A company buys a delivery van for $48,000, paying $18,000 from its bank account and financing the remaining $30,000 with a loan from the dealer. The entry debits Motor Vehicles by $48,000 to record the new asset, credits Cash at Bank by $18,000 for the money that left, and credits Loan Payable by $30,000 for the new obligation.
The check is that the credits of $18,000 + $30,000 = $48,000 equal the single debit of $48,000, so the entry balances. A month later the van begins to be depreciated over five years, which is $48,000 / 60 months = $800 per month. That second entry debits Depreciation Expense by $800 and credits Accumulated Depreciation by $800, again balancing.Case study
Seen in the real world.
Ravensworth Tools is an illustrative hand tool maker used here to show how entries go wrong. Its finance assistant posted a $90,000 equipment purchase entirely to repairs expense instead of to fixed assets, because the supplier invoice was headed workshop works. Profit for the month came in $90,000 below budget and the operations director spent two days hunting for a cost overrun that did not exist.
The fix was a single correcting entry: debit Plant and Equipment $90,000, credit Repairs Expense $90,000, with a note explaining the original error and a copy of the invoice attached. Depreciation then had to be caught up over the remaining life of the asset. The fictional company also added a rule that any single invoice above $25,000 needed a second pair of eyes before posting, which is the kind of control most finance teams build after exactly this sort of afternoon.
Watch out
Common mistakes.
- Thinking a debit always means money going out. A debit simply means the left column, and it records an increase in an asset as often as it records a cost.
- Posting a manual entry with no supporting document. If nobody can explain the entry three months later, the audit trail is effectively broken.
- Forcing an entry to balance with a plug figure to a suspense account and then never clearing that account.
Questions
People also ask.
What is the difference between a journal entry and a ledger?
The entry is the individual record of a transaction, while the ledger is the running total of all entries grouped by account.
Why do auditors focus on manual entries?
Because automated entries follow a fixed pattern, whereas manual ones are where deliberate manipulation or simple keying errors usually appear.
Can an entry have more than two lines?
Yes, an entry can touch many accounts at once, provided the total debits still equal the total credits.
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