Single Entry System of Bookkeeping: Meaning, Example and Rules

TL;DR: The single entry system of bookkeeping records each transaction once, usually as money in or money out in a cash book, without a matching debit and credit. It is quick and cheap for a tiny cash business, but it cannot produce a balance sheet or catch errors, and in India it is not allowed for companies (Companies Act 2013, section 128) or for anyone who crosses the income-tax book-keeping limits.

The single entry system of bookkeeping is a method of recording business transactions where each transaction is entered only once, typically in a cash book or a list of receipts and payments, instead of being posted to two accounts as a debit and a credit. A shopkeeper who writes "Sold goods, ₹3,000 received" in a notebook and keeps a running cash balance is using single entry. Profit is worked out at year end by comparing capital at the start and end of the year (the statement of affairs method), not from a full set of ledger accounts.

What are the three types of incomplete records?

Textbooks, including the ICAI Foundation study material chapter on accounts from incomplete records, describe three forms:

Quasi single entry is the most common in practice: a small trader keeps a cash book, a sales register and a khata of who owes what, but never posts these to a ledger.

Example: a stationery shop's April cash book

A single entry cash book has five columns: date, description, receipts, payments and a running balance. There is no Dr/Cr column and no ledger folio, because nothing is posted anywhere else.

Riya runs a stationery shop in Pune. She starts April with ₹50,000 cash. Her April cash book under single entry:

Cash rose by ₹19,000, or 38%. That is not her profit. The ₹40,000 loan belongs in a Bank Loan A/c (a liability), the ₹9,000 rack in Furniture A/c (an asset), the ₹5,000 in Drawings A/c, and the ₹12,000 collection belongs to a March sale. Her April cash-basis operating result is ₹18,000 sales minus ₹22,000 purchases minus ₹15,000 rent, a loss of ₹19,000 on cash, even though she may have closing stock worth more than she bought. A single entry book alone cannot tell her which is true. This is the core weakness every top-ranking page mentions; the example shows how large the error can be.

How do you calculate profit from incomplete records?

Profit under single entry is calculated with the statement of affairs (net worth) method: list assets and liabilities at the start and end of the year, take the difference as capital, then adjust for what the owner put in and took out.

Profit = Closing capital − Opening capital + Drawings − Additional capital introduced

Worked example for Riya's full year (figures in ₹):

Drawings during the year: ₹60,000. Fresh capital introduced: ₹20,000.

Profit = 1,77,000 − 1,32,000 + 60,000 − 20,000 = ₹85,000

On opening capital of ₹1,32,000 that is a return of about 64%. Notice what the method hides: stock rose 58% (₹60,000 to ₹95,000) and debtors rose 67% (₹12,000 to ₹20,000). Both count as profit here, so if the closing stock was counted generously or ₹8,000 of debtors will never pay, profit is overstated rupee for rupee.

The method gives one number. It cannot tell Riya whether margins fell, which expense grew, or whether stock was miscounted, because there are no sales, purchase or expense accounts behind it. Converting the records into a trading and profit and loss account needs the missing figures to be rebuilt from the cash book and debtor and creditor lists, which is the "conversion into double entry" exercise accountants do at year end.

Single entry system of bookkeeping vs double entry: what is the difference?

Double entry records every transaction in at least two accounts, with total debits equal to total credits, so that assets = liabilities + equity after every entry. The golden rules of accounting decide which account is debited and which is credited.

Is it legal for an Indian business to keep books this way?

The single entry system is legal only for businesses that are not companies and that stay below the income-tax and GST record-keeping requirements.

• Companies: Section 128(1) of the Companies Act, 2013 requires books "on accrual basis and according to the double entry system of accounting". Single entry is not an option for a private limited company or an OPC. LLPs have a similar double entry requirement under the LLP Rules.
• Income tax, until FY 2025-26: Section 44AA of the Income-tax Act, 1961 and Rule 6F required specified professionals (doctors, lawyers, CAs, architects and others) with gross receipts above ₹1.5 lakh in each of the three previous years to keep a cash book, journal and ledger. Other individuals and HUFs in business had to keep books if income exceeded ₹2.5 lakh or turnover exceeded ₹25 lakh in any of the three preceding years (TaxGuru summary).
• Income tax, from 1 April 2026: the Income-tax Act, 2025 replaced the 1961 Act. Section 62 now carries the book-keeping requirement and Rule 46 of the Income-tax Rules, 2026 consolidates the old Rule 6F list of books (TaxGuru on section 62). Most pages on single entry still cite only section 44AA. Check the notified Rule 46 for your profession before relying on the old limits.
• GST: Section 35 of the CGST Act requires every registered person to keep accounts of supplies, stock, input tax credit and output tax, and section 36 requires them to be kept for 72 months (about 2,190 days) from the due date of the annual return. A plain cash book does not show input tax credit or tax payable, so a GST-registered business needs at least purchase and sales registers with tax columns, which in practice means moving to double entry.

Why do small traders still use it?

• Simple: no debits, credits or ledgers to learn. Anyone who can keep a diary can keep the cash book.
• Cheap: a notebook or a spreadsheet is enough, and no accountant is needed day to day.
• Fast: one line per transaction.
• Enough for very small cash businesses: a sole proprietor below the tax book-keeping limits, not registered for GST, with no stock and no credit sales can get by.

Where does it break down?

• No arithmetic check: without a trial balance, a missed or mistyped entry goes unnoticed.
• No true profit: profit is an estimate from capital change, and the April example shows cash change can mislead badly.
• No balance sheet from the books: assets and liabilities are counted, not recorded.
• Weak for loans: banks ask for a profit and loss account and balance sheet, usually audited or CA-certified for larger limits.
• Fraud and theft go unseen: with no control accounts, missing stock or cash is hard to trace.
• Fails compliance: unusable for companies and for anyone above the tax and GST record-keeping requirements.

When should you move to double entry?

Switch to double entry as soon as any of these happens:

1. You register as a company or LLP.
2. You register for GST and need to track input tax credit and output tax.
3. Your income or turnover nears the income-tax book-keeping limits.
4. You start selling on credit or holding stock worth tracking.
5. You plan to apply for a bank loan or overdraft.

The switch is mechanical: take the statement of affairs on the switch date as your opening balances (cash, bank, debtors, stock, fixed assets, creditors, loans, capital), then record every transaction from that date as a journal entry: a cash sale becomes Cash A/c Dr / Sales A/c Cr, rent paid becomes Rent A/c Dr / Cash A/c Cr, and a GST sale adds an Output CGST and Output SGST credit. Debtors and creditors, which single entry kept as a khata, become Sundry Debtors and Sundry Creditors control accounts. Accounting software does the second step automatically. Owner withdrawals go to a drawings account, and fixed assets are written down through depreciation. At year end, the ledger balances feed a trial balance, a profit and loss account and a balance sheet.

If you want the double entry done without learning it, the LuckPanda Finance ledger posts each invoice, bill and payment to both sides automatically.