How double-entry accounting works (in plain language)
Debits, credits, the accounting equation and why every transaction touches two accounts — explained with examples a founder can follow.
The short answer
Double-entry accounting records every transaction in at least two accounts so that total debits always equal total credits; this keeps the accounting equation (assets = liabilities + equity) in balance and makes errors detectable. It is the basis of every trial balance, profit and loss and balance sheet.
The one rule
Every transaction has two sides. When you pay 100 KWD of rent from the bank, rent expense goes up by 100 and bank goes down by 100. Record both, and the books stay in balance. That is the whole idea; the vocabulary is what makes it feel harder than it is.
The accounting equation
**Assets = Liabilities + Equity.** What you own equals what you owe plus what belongs to the owners. Income increases equity; expenses decrease it. Because every entry changes two sides by the same amount, the equation always holds — and a trial balance that doesn't balance tells you something was entered wrong.
Debits and credits, without the mysticism
| Account type | Increases with | Decreases with |
|---|---|---|
| Assets (cash, bank, receivables, equipment) | Debit | Credit |
| Expenses (rent, salaries, software) | Debit | Credit |
| Liabilities (payables, loans, VAT owed) | Credit | Debit |
| Equity (capital, retained earnings) | Credit | Debit |
| Income (sales, fees) | Credit | Debit |
“Debit” and “credit” are just the left and right columns of an entry; they don't mean good or bad. Memorise the table above and you can read any journal entry.
Four everyday entries
- **Pay rent 100 KWD from the bank.** Debit Rent expense 100 · Credit Bank 100.
- **Issue an invoice 500 KWD to a client.** Debit Accounts receivable 500 · Credit Sales 500. (With 15% VAT: Debit receivable 575 · Credit Sales 500 · Credit VAT payable 75.)
- **Client pays the invoice.** Debit Bank 500 · Credit Accounts receivable 500.
- **Buy a laptop 400 KWD on the company card.** Debit Equipment (asset) 400 · Credit Card payable 400.
Why it beats a single list of transactions
- **Errors surface.** A missed side throws the trial balance out of balance.
- **Reports fall out of the data.** P&L is income and expense accounts; balance sheet is assets, liabilities and equity; cash flow is derived from the movements. No separate spreadsheets.
- **Accrual timing works.** An invoice issued in July and paid in August is one receivable created and then settled, not two confusing income lines.
- **Accountants can review it.** Double-entry is the common language of every accountant and auditor.
Do you need to know this to use Qaid?
No — and that is the point. You describe the rent payment; Qaid proposes “Debit Rent 100 / Credit Bank 100”, explains why, and you approve it. The ledger and reports page lists what you get from that: trial balance, P&L, balance sheet, cash flow, ageing and VAT reports. Knowing the rule above simply lets you check the draft in five seconds.