Source Documents and Vouchers

In the previous chapter, "The Modern Approach to Debit and Credit," we learned the rules for classifying accounts and deciding which one goes up and which one goes down. But in the real world of business, you cannot simply wake up, open your accounting software, and type in, "I paid ₹10,000 for rent today."

If you could do that, anyone could manipulate their books to show massive fake expenses, wipe out their profits, and pay zero tax.

To prevent this, accounting relies on a foundational rule called the Principle of Verifiable Objective Evidence. This principle states that every single transaction recorded in the books of accounts must be supported by physical, objective proof. You cannot record a journal entry based on a verbal promise, a memory, or a guess. You need a piece of paper that proves the event actually happened, shows the exact date, and confirms the exact amount.

This chapter is about that paperwork. We are going to look at the raw evidence of business (Source Documents) and how accountants translate that raw evidence into the language of debits and credits (Vouchers) before a single journal entry is ever written.

The Raw Proof: What is a Source Document?

A source document is the very first record of a business transaction. It is the original piece of paper (or digital file) that is created at the exact moment a transaction takes place.

Think of a source document as the "receipt" you get when you buy groceries, the "ticket" you get when you board a bus, or the "bill" a plumber hands you after fixing a pipe. In business, these documents are carefully collected and filed because they are the ultimate defense if a tax inspector or an auditor ever asks, "How do I know this transaction is real?"

Let us look at the most common source documents you will encounter in accounting.

1. The Cash Memo (For Cash Transactions)

When a business sells goods for immediate cash, it issues a Cash Memo. If you walk into a stationery shop, hand over ₹500 in cash, and buy a calculator, the shopkeeper will hand you a cash memo. It acts as proof that goods were sold and cash was received right then and there.

A cash memo typically contains:

• The name and address of the seller.
• The date of the transaction.
• A description of the goods, quantity, and rate.
• The total amount received (including any taxes like GST).
• The signature of the cashier or authorized person.

2. The Invoice or Bill (For Credit Transactions)

What happens if you buy that same calculator, but you tell the shopkeeper, "I will pay you next month"? The shopkeeper will not issue a cash memo, because no cash changed hands. Instead, they will issue an Invoice.

An invoice is the source document for a credit sale or a credit purchase.

• When a business sells goods on credit, it prepares a Sales Invoice and gives the original to the customer, keeping a carbon copy for its own records.
• When a business buys goods on credit, it receives a Purchase Invoice (which the seller might just call a "bill").

3. The Receipt (For Payments Received)

When a customer who bought goods on credit finally comes back a month later to pay their debt, what document is generated? It cannot be a cash memo (the goods were already sold a month ago). It cannot be an invoice (that was already issued).

Instead, the business issues a Receipt. A receipt is a written acknowledgment that cash or a cheque has been received from a customer. It proves that a specific debt has been settled, either fully or partially.

4. The Pay-in Slip (For Bank Deposits)

If you have ever visited a branch of SBI, HDFC, or J&K Bank to deposit cash or a cheque into an account, you have filled out a Pay-in Slip.

This is a form provided by the bank. It has two parts, separated by a perforated line. You fill out the details (date, account number, amount, denomination of notes) on both sides. You hand the whole slip and the cash to the bank teller. The teller stamps both sides, keeps the main portion for the bank's records, and tears off the smaller portion—called the counterfoil—and hands it back to you.

For the business's accountant, that stamped counterfoil is the source document proving that money was deposited into the bank.

5. The Cheque (For Bank Payments)

A cheque is a written order to a bank, instructing it to pay a specific sum of money to the person named on the cheque. When a business pays its rent by cheque, the details of that cheque (recorded on the chequebook's counterfoil or record slip) serve as the source document for the payment.

6. Debit Notes and Credit Notes (For Returns and Adjustments)

Sometimes, things go wrong after an invoice is issued. Goods might be damaged, or there might be an overcharge.

• Debit Note: If a business buys goods on credit and returns some of them because they are defective, the business sends a Debit Note to the supplier. It essentially says, "I am returning these goods, so I am debiting (reducing) the amount I owe you in my books."
• Credit Note: If a customer returns defective goods to the business, the business sends the customer a Credit Note. It says, "I have received the returned goods, and I am crediting (reducing) the amount you owe me in my books."

The Bridge to the Books: What is a Voucher?

Now, imagine you are the accountant for a company. The sales manager walks into your office and drops a massive pile of cash memos, invoices, receipts, and pay-in slip counterfoils onto your desk.

Can you just pick up a cash memo and write a journal entry?

Technically, you have the proof. But a cash memo is just a raw piece of paper from a shop. It does not speak the language of accounting. It does not say "Debit the Printing & Stationery Account" or "Credit the Cash Account." It just says "10 Reams of A4 Paper - ₹2,000."

Before you can record this in the official accounting books, you need to translate that raw source document into an accounting instruction. This translation happens on a document called a Voucher.

Think of a voucher as a "cover sheet" for the source document. The accountant takes a blank voucher form, writes down exactly which account to debit and which to credit, and then physically staples the source document (like the cash memo) to the back of it. Then, a senior manager or the business owner signs the voucher to authorize it. Only after it is signed does the transaction get entered into the journal.

Types of Accounting Vouchers

Because businesses deal with both cash and non-cash transactions, vouchers are broadly divided into two main categories: Cash Vouchers and Non-Cash (or Journal) Vouchers.

1. Cash Vouchers

Cash vouchers are prepared only for transactions that involve the immediate receipt or payment of cash (or bank/cheque transactions). They are further divided into two types, and their names can sometimes confuse students, so pay close attention to the logic here.

A) Debit Vouchers (For Cash Payments) When a business pays cash out, it prepares a Debit Voucher. Why is it called a Debit Voucher? Think about the accounting entry for paying rent in cash. You Debit Rent Account, and you Credit Cash Account. Because the "Credit Cash" part is obvious and automatic for every single cash payment, the voucher's main job is to tell the accountant which account to debit (in this case, Rent). Therefore, it is called a Debit Voucher.

• Used for: Paying salaries, buying goods for cash, paying creditors, buying assets for cash.
• Source documents attached: Cash memos from suppliers, receipts signed by the payee.

B) Credit Vouchers (For Cash Receipts) When a business receives cash, it prepares a Credit Voucher. Why is it called a Credit Voucher? Think about the entry for receiving cash from a customer. You Debit Cash Account, and you Credit the Customer's Account. Since the "Debit Cash" part is automatic for every cash receipt, the voucher focuses on telling the accountant which account to credit. Therefore, it is called a Credit Voucher.

• Used for: Cash sales, receiving cash from debtors, selling an old asset for cash, withdrawing cash from the bank.
• Source documents attached: Carbon copies of cash memos issued to customers, carbon copies of receipts issued.

2. Non-Cash Vouchers (Transfer Vouchers / Journal Vouchers)

What if a transaction does not involve cash at all? For example, buying machinery on credit, or recording the depreciation (wear and tear) of an asset at the end of the year.

For these, we use Non-Cash Vouchers, commonly called Journal Vouchers or Transfer Vouchers. Since there is no automatic cash debit or credit involved, a Journal Voucher must explicitly state both the account to be debited and the account to be credited.

• Used for: Credit purchases, credit sales, returning goods, depreciation, rectifying accounting errors.
• Source documents attached: Invoices, bills, debit notes, credit notes.

The Lifecycle of a Transaction

To truly understand how all these pieces fit together, let us look at the step-by-step lifecycle of a single business event.

Notice how the journal entry is the last step in this process. The books of accounts are sacred; nothing enters them without passing through the filter of a source document and an authorized voucher.

Worked Example: A Day in the Office

Let us walk through a few practical scenarios to see how a business owner, let's call her Priya, handles her paperwork. Priya runs a wholesale clothing business.

Scenario 1: Priya pays ₹5,000 cash for office electricity.

• The Event: Paying the electricity bill.
• The Source Document: The official receipt stamped by the Power Development Department (PDD).
• The Voucher: Priya's accountant takes a Debit Voucher (because cash is going out). The accountant writes "Debit Electricity Expense A/c: ₹5,000". The PDD receipt is stapled to the back. Priya signs it.

Scenario 2: Priya sells ₹20,000 worth of clothes to a retailer, Rahul, on 30-day credit.

• The Event: A credit sale.
• The Source Document: Priya's billing software generates a Sales Invoice. She gives the original to Rahul and keeps a copy.
• The Voucher: Because no cash is involved, the accountant prepares a Journal Voucher (Non-Cash Voucher). It says "Debit Rahul's A/c, Credit Sales A/c". The copy of the invoice is attached.

Scenario 3: Rahul comes back 30 days later and hands Priya a cheque for ₹20,000.

• The Event: Receiving payment via cheque.
• The Source Document: Priya issues a Receipt to Rahul to prove he paid. She also fills out a Pay-in Slip at her bank to deposit the cheque, keeping the stamped counterfoil. Both the receipt copy and the counterfoil act as source documents.
• The Voucher: The accountant prepares a Credit Voucher (because money is coming in). It says "Credit Rahul's A/c: ₹20,000". The source documents are attached.

By following this strict paper trail, Priya ensures that if an auditor ever questions her electricity expenses or her sales figures, she has a perfectly organized file of vouchers, each backed by undeniable physical evidence.

Quick Revision

• Principle of Objective Evidence: Every accounting entry must be supported by verifiable proof. You cannot record transactions based on memory or verbal claims.
• Source Document: The raw, original proof of a transaction (e.g., cash memo, invoice, receipt). It proves the event happened.
• Cash Memo: Issued for immediate cash sales/purchases.
• Invoice / Bill: Issued for credit sales/purchases (payment to be made later).
• Pay-in Slip: The bank form used to deposit cash or cheques; the stamped counterfoil is the business's source document.
• Voucher: An internal accounting document that translates the source document into debits and credits, authorizing the journal entry.
• Debit Voucher: Used for cash payments (tells the accountant what to debit).
• Credit Voucher: Used for cash receipts (tells the accountant what to credit).
• Journal / Non-Cash Voucher: Used for transactions not involving cash, like credit sales or depreciation.
• The Golden Sequence: Event → Source Document → Voucher → Journal Entry.