Quick answer
Adjusting entries are period-end journal entries that update account balances for economic activity, allocations, or estimates not fully captured by routine recording. They may recognize accruals, update deferrals, or record allocations and estimates; they are not automatically corrections of mistakes.
The unadjusted trial balance is a checkpoint, not the finished reporting record. At period end, the business checks whether recorded balances reflect what has been earned, used, owed, or still available as at the reporting date. Identified adjustments are journalized and posted before the adjusted trial balance is prepared.
An accrual records revenue earned or an expense incurred before the related routine billing, collection, or payment entry. A deferral updates an amount left from an earlier cash receipt or payment as the business provides the service or uses the asset.
Why adjustments matter
Routine entries cannot always capture activity by the reporting date. Invoices may not have arrived, billing may occur later, a prepaid asset may have been partly used, or an estimate may need updating. Without the adjustment, the period could omit revenue or expense and leave the related asset or liability overstated or understated. Adjustments align the records with the economic activity that belongs to the period before the statements are prepared.
Where adjustments fit in the cycle
- Start with the ledger and unadjusted trial balance.
- Gather period-end evidence such as counts, contracts, schedules, and calculations.
- Identify which accounts are not up to date and determine the amount supported by the evidence.
- Prepare and post a balanced adjusting entry.
- Prepare the adjusted trial balance used for financial statements.
Period-end timing adjustments ordinarily do not use Cash. A cash receipt or payment is recorded when it happens; the adjustment recognizes or allocates the related non-cash balance. A correction can involve Cash, but that is a different reason for an entry.
From timing pattern to adjusting entry
Two questions organize the most common adjustments: did cash or the routine entry happen before recognition, or will it happen afterward? Then identify whether the missing effect concerns revenue, an expense, or an allocation or estimate.
- Update a recorded asset or liability
- The related receipt, payment, or credit transaction was recorded earlier. The adjustment recognizes the portion now earned or used—for example, supplies consumed or unearned revenue now earned.
- Recognize an accrual
- Revenue has been earned or an expense incurred before the routine billing, collection, or payment entry—for example, a receivable or wages payable.
- Record an allocation or estimate
- A supported calculation brings the period’s expense and related balance up to date. Depreciation and some allowance estimates use this pattern.
| Pattern | What period-end evidence shows | Typical debit | Typical credit |
|---|---|---|---|
| Prepaid expense used | Cash was paid earlier; part of the recorded asset has now been consumed. | Expense | Prepaid asset |
| Unearned revenue earned | Cash was received earlier; part of the promised service has now been provided. | Unearned Revenue | Revenue |
| Accrued revenue | Revenue was earned before routine billing or collection. | Receivable | Revenue |
| Accrued expense | An expense was incurred before routine billing or payment. | Expense | Payable |
| Allocation or estimate | A supported schedule or estimate shows the period’s amount. | Expense or loss | Related asset offset, liability, or allowance |
The account names vary with the facts, but the direction does not come from memorizing a list. Identify what has now been earned, used, owed, or estimated, then update the balance-sheet account that carried the timing difference.
Maple Tech’s three March adjustments
At March 31, $900 of supplies remains. Maple has completed all required performance for $1,000 of services and has an unconditional right to the amount. Its stated equipment policy produces one month of depreciation. These facts illustrate a used asset, accrued revenue, and an allocation. The comparison above also shows the corresponding liability patterns that do not arise in Maple’s March facts.
| Account | Debit | Credit |
|---|---|---|
| Supplies Expense | 1,500 | |
| Supplies | 1,500 |
Supplies used: $2,400 recorded − $900 counted on hand = $1,500 March expense.
| Account | Debit | Credit |
|---|---|---|
| Accounts Receivable | 1,000 | |
| Service Revenue | 1,000 |
All required performance is complete and issuing the invoice is only an administrative step, so Maple records its unconditional right to the amount as Accounts Receivable.
| Account | Debit | Credit |
|---|---|---|
| Depreciation Expense | 200 | |
| Accumulated Depreciation — Equipment | 200 |
Monthly allocation: ($12,000 cost − $0 residual value) ÷ 60 months = $200.
The adjusted trial balance
| Account | Debit | Credit |
|---|---|---|
| Cash | 42,500 | |
| Accounts Receivable | 1,000 | |
| Supplies | 900 | |
| Equipment | 12,000 | |
| Accumulated Depreciation — Equipment | 200 | |
| Accounts Payable | 2,400 | |
| Common Shares | 50,000 | |
| Service Revenue | 7,000 | |
| Rent Expense | 1,500 | |
| Supplies Expense | 1,500 | |
| Depreciation Expense | 200 | |
| Total | 59,600 | 59,600 |
The columns now total $59,600. The $1,000 accrued service and $200 depreciation entries add $1,200 to each column. The $1,500 supplies adjustment moves an amount between two debit-balance accounts, so it does not change either total.
Financial-statement effect
| Statement | Account | Effect | Timing |
|---|---|---|---|
| Income statement | Revenue and expenses | March profit becomes $3,800 | For March |
| Balance sheet | Receivable, supplies, accumulated depreciation | Period-end carrying amounts are updated | At March 31 |
| Cash flow statement | Cash | No adjustment changes the $42,500 cash balance | Cash changes only when money moves |
Balanced is still not enough
Each adjusting entry must balance, but equal debits and credits do not establish that the evidence, account choice, period, or estimate is correct. Review the reasoning before posting.
Common mistakes
- Waiting for cash before recognizing activity that belongs to the period.
- Adjusting the full recorded balance instead of only the amount earned, used, or still outstanding.
- Crediting Equipment directly for depreciation instead of using the accumulated-depreciation contra-asset in this example.
- Preparing statements from the unadjusted trial balance after adjustments were identified.
See Accrual Accounting for the timing logic, Depreciation for the equipment allocation, and Trial Balance for the three accounting-cycle checkpoints.