Debits, credits and T-accounts: how a transaction preserves balance equality

Debit is the left side of an account and credit is the right. They are not synonyms for receipt and payment. In our educational system, an increase in an asset is debited and a decrease credited; an increase in liabilities and equity is credited and a decrease debited. Expense accumulates on the debit side of an expense account and income on the credit side of an income account. Bank-statement labels may feel different because a bank keeps its own books: first identify whose accounting system you are reading.

The side of an entry does not mean good or bad

Double-entry requires total debits and credits of every transaction to be equal. It makes the other side of a change traceable, but does not prove that the event occurred or that the measurement is correct. A receivable and revenue can be overstated together while equality remains. Therefore, inspect the journal with contracts and evidence of performance, not instead of them.

Journal: from owner contribution to customer payment

All amounts are fictional; taxes, interest and inventory are excluded. The workshop starts from zero. The owner contributes 100, then the workshop buys equipment for 60, provides services for 50 on credit and receives 30 from the customer. It consumes maintenance of 12 without paying yet and records depreciation of 6. We assume the basis for recognising every transaction has been established; local chart-of-accounts numbers are not used.

| Event | Debit | Credit | Amount | |---|---|---|---:| | Owner contribution | Cash | Equity | 100 | | Equipment purchase | Equipment | Cash | 60 | | Performed service | Receivable | Revenue | 50 | | Partial collection | Cash | Receivable | 30 | | Maintenance consumed | Maintenance expense | Payable | 12 | | Equipment resource consumed | Depreciation expense | Accumulated depreciation | 6 |

Each row has both sides. Receiving 30 does not create a second revenue: it reduces an existing receivable. Buying equipment is not wholly an expense in this model: the resource is used later. Maintenance, by contrast, has already been consumed although the supplier has not been paid. Accrual is thus separated from payment timing, not from evidence of the event itself.

T-account: turnovers and balances are different amounts

A T-account is a compact picture of two sides. For cash, the left side contains 100 and 30 and the right side 60: debit turnover is 130, credit turnover 60 and ending debit balance 70. For receivables, the sides are 50 and 30, leaving 20. Equipment has 60 on the left and nothing on the right. Accumulated depreciation of 6 is held in a separate contra-account with a credit balance: net equipment value is 54.

| Account | Debit turnover | Credit turnover | Ending balance | |---|---:|---:|---| | Cash | 130 | 60 | Debit 70 | | Equipment | 60 | 0 | Debit 60 | | Receivable | 50 | 30 | Debit 20 | | Maintenance expense | 12 | 0 | Debit 12 | | Depreciation expense | 6 | 0 | Debit 6 | | Equity | 0 | 100 | Credit 100 | | Revenue | 0 | 50 | Credit 50 | | Payable | 0 | 12 | Credit 12 | | Accumulated depreciation | 0 | 6 | Credit 6 |

Aggregate turnovers equal 258 on each side; ending debit and credit balances total 168. Do not require the two sides of each individual account to be equal: their difference is the balance. Confusing turnovers and balances is a common reason for an incorrect “reconciliation”.

Closing the result and linking statements

In simplified form, close revenue with “Dr Revenue 50 — Cr Result 50”, expenses with “Dr Result 18 — Cr Expenses 18”, then profit with “Dr Result 32 — Cr Retained earnings 32”. These are educational account names, not a mandatory national chart. After closing, net assets are 70 + 20 + 54 = 144; liabilities are 12; equity is 100 + 32 = 132: both balance-sheet sides equal 144.

Cash increased by 70: operating receipts 30, investing purchase minus 60 and owner financing plus 100. Profit of 32 is not operating cash of 30. In our model, the indirect reconciliation is 32 + 6 − 20 + 12 = 30. The official IAS 7 overview describes cash-flow groups and indirect adjustments; IAS 1 describes a set of statements. Those support the link between statements, while the journal example and T-accounts are an independent editorial model, not a quotation from the standards.

How to find an error when the balance agrees

First check the performance period and amount, then the corresponding account. If a payment on an old receivable is mistakenly recorded as new revenue, arithmetic equality remains but the receivable history is wrong. If maintenance is capitalised without a basis, expenses are understated. For each event ask: what resource or obligation actually changed, and what supports it?

Do not use matching totals as an audit opinion. This example does not address VAT, foreign-exchange differences, revaluation or complex contracts. Continue with [three-statement links](/guides/three-statement-links/); real-organisation entries require the applicable standard, facts and qualified review.

Educational financial mechanisms; IFRS, U.S. materials and OECD recommendations are explicitly distinguished; not Russian rules and not a professional opinion.

Source references retained: formulas, figures, caveats, links and jurisdictional qualifications are preserved.