Why is "Recording trade discount as a separate entry in the books." a common mistake in Business documentation?

Why it happens: Students see a percentage discount and reach for a 'Discount Allowed' or 'Discount Received' entry by reflex. How to avoid it: Trade discount is *part of the price negotiation* — it never enters the books. Only the net invoice figure is recorded. **Memorise:** 'Trade discount = invoice prep. Cash discount = ledger entry.' Source: Edexcel 4AC1 examiner reports flag this annually.

Why is "Calculating cash discount on the list price rather than on the invoice total (after trade discount)." a common mistake in Business documentation?

Why it happens: Sequence error — students apply both percentages independently to the list price. How to avoid it: Always apply trade discount FIRST to get the invoice total, THEN apply cash discount to that figure.

Why is "Confusing credit notes (issued by seller) and debit notes (sent by buyer)." a common mistake in Business documentation?

Why it happens: Both adjust trade balances; the names sound similar. How to avoid it: Credit note = the SELLER issues it to CREDIT the customer's account (reduce the debt). Debit note = the BUYER may send to request a credit note. The credit note is the one that drives the books.

Why is "Treating a purchase order or delivery note as the source document for the Purchases Day Book." a common mistake in Business documentation?

Why it happens: These documents precede the invoice and feel 'first'. How to avoid it: Purchases Day Book is triggered by the **invoice** — the demand for payment. Orders and delivery notes are evidence trails but do not result in a ledger entry.

Why is "Using the bank statement as the primary source for the Cash Book." a common mistake in Business documentation?

Why it happens: It's the most complete record of bank activity. How to avoid it: The Cash Book is the business's OWN record, written from cheque counterfoils, paying-in slips and remittance advices. The bank statement is the BANK's record — used afterwards to RECONCILE the Cash Book (Topic 3).

Why is "Treating a statement of account as a source document for an entry." a common mistake in Business documentation?

Why it happens: It is a formal document sent by the seller. How to avoid it: A statement of account is a **summary** of transactions already recorded. It does not generate new entries — it is used to reconcile the customer's records with the supplier's.

Why is "Forgetting that VAT is calculated AFTER trade discount but BEFORE cash discount." a common mistake in Business documentation?

Why it happens: Three-step pricing is complex under time pressure. How to avoid it: Standard UK order: List price → less trade discount → add VAT → invoice total. Cash discount, if taken, is then deducted from the invoice total at settlement.

Introduction to Book KeepingPearson Edexcel IGCSE Accounting 4AC1

Business documentation

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Business Documentation — Edexcel IGCSE Accounting (4AC1) Detailed Notes

Every transaction in this course begins with a source document. Learn which document evidences each transaction, the calculation logic on an invoice (trade vs cash discount), and the flow into books of original entry.

What you’ll learn

Mapped to the Pearson Edexcel IGCSE 4AC1 syllabus (2026 onwards).

Identify the main source documents used in business transactions.
Explain the purpose of each source document and the entries it triggers.
Distinguish between trade discount and cash discount and calculate each correctly.
Trace the flow of documents from order through delivery, invoicing and settlement.
Recognise the role of the bank statement and statement of account as reconciliation tools rather than primary source documents.

What is a source document and why does it matter?

Source documents are the audit trail — the line between bookkeeping and fraud.

A source document is the original written or electronic record of a transaction. It is the evidence that a transaction happened, the figures involved, the date, and the parties. In accounting:

Source documents come before the books of original entry.
They form the audit trail — auditors trace every figure in the financial statements back to a source document.
Without source documents, an entry has no support and the auditor will challenge it.

For each transaction type, you must know:

Which document is the source.
Who issues it (buyer or seller).
Which book of original entry it flows into.
Which ledger accounts are updated.

Source = evidence + figures + date + parties.
Sits before books of original entry in the audit trail.
Drives both the entry and the figure recorded.

The main source documents — what each does

Eight documents to memorise. Know the issuer, recipient and the entry each triggers.

Document	Issued by	Issued to	Purpose	Book of original entry
Sales invoice	Seller	Buyer	Demand payment for credit sale	Sales Day Book
Purchase invoice	Seller	Buyer	(Same invoice, from buyer's viewpoint)	Purchases Day Book
Credit note (sales)	Seller	Buyer	Reduce buyer's debt — return/overcharge	Sales Returns Day Book
Credit note (purchase)	Seller	Buyer	(Same, from buyer's viewpoint)	Purchases Returns Day Book
Cheque counterfoil	Drawer (payer)	Bank	Evidence of cheque written	Cash Book (Cr Bank)
Paying-in slip / counterfoil	Account holder	Bank	Evidence of bank deposit	Cash Book (Dr Bank)
Receipt	Seller	Buyer	Evidence of cash received	Cash Book (Dr Cash)
Petty cash voucher	Petty cashier	Claimant	Authorise small cash payment	Petty Cash Book

Documents that are NOT primary source documents but are evidence trails:

Purchase order — request to supply; no entry yet.
Delivery note — goods received; used to verify the invoice.
Statement of account — monthly summary; used to reconcile.
Bank statement — bank's record; used for reconciliation (Topic 3).
Debit note — buyer's notification of intention to return goods; the credit note issued in response is what drives the books.

Memorise the issuer → recipient → book triple for each.
Invoice & credit note drive the Day Books; Cash/cheque documents drive the Cash Book.
Statements and bank statements are RECONCILIATION tools.

Inside an invoice — the numbers that matter

Standard invoice sequence: list price → trade discount → VAT → invoice total → cash discount terms.

An invoice contains the figures that drive the ledger entry. The standard build-up (UK/IGCSE convention):

List price (catalogue price × quantity).
Less trade discount (a percentage discount for bulk or trade-partner status). Deducted on the invoice; NOT recorded.
= Net price (the figure that enters the books).
Add VAT at the applicable rate (where VAT is examined).
= Invoice total payable.
Terms note the cash discount offered (e.g., '2.5% if paid within 10 days').

The seller records:

Dr Customer (Sales Ledger) — Invoice total
Cr Sales — Net price
Cr VAT (where applicable) — VAT amount

The buyer mirrors this.

Trade discount sits on the invoice (not in the books); VAT is applied to the net price; cash discount is conditional on early payment.

The trade vs cash discount distinction — exam-critical

Possibly the single most-confused topic in all of Paper 1 — drill the difference.

Feature	Trade Discount	Cash Discount
Purpose	Bulk-buy or trade-partner reduction	Reward for early settlement
Where shown	On the invoice	Conditional — only if paid early
Recorded in books?	NO — never enters ledgers	YES — Discount Allowed / Discount Received
Calculated on	List price	Invoice total (net of trade discount)
Example	20% off 100 units × £50 list → £4,000 invoice	2.5% of £4,000 = £100 if paid in 10 days

Discount Allowed (seller's view): an expense — the seller has 'given up' £100 of income to encourage prompt payment.

Discount Received (buyer's view): an income — the buyer has 'gained' £100 by paying promptly.

Trade discount: NOT in the books, sets the invoice price.
Cash discount: IN the books, conditional on early payment.
Cash discount is calculated on the NET (after trade discount) invoice total.
Discount Allowed = expense to seller. Discount Received = income to buyer.

Credit notes — the second-most-tested document

Issued by the seller to reduce a customer's debt.

A credit note is issued by the seller to reduce the amount the customer owes. Reasons include:

Return of goods (faulty, wrong item, damaged).
Overcharge on the original invoice.
Allowance for minor damage that the buyer accepts.
Quantity discount applied retrospectively.

Seller's entries (source: credit note issued):

Dr Sales Returns / Returns Inwards
Cr Customer (Sales Ledger)

Buyer's entries (source: credit note received):

Dr Supplier (Purchases Ledger)
Cr Purchases Returns / Returns Outwards

Credit notes feed into the Returns Day Books — Sales Returns Day Book for seller, Purchases Returns Day Book for buyer.

The document trail of a credit transaction

A standard end-to-end flow — examiners love this question.

Walk through a credit sale step by step:

Purchase order — buyer to seller.
Delivery note — seller to buyer, signed on receipt.
Sales invoice — seller to buyer → Sales Day Book entry.
Statement of account — seller to buyer monthly → used to reconcile.
Cheque / bank transfer / cash receipt — buyer to seller → Cash Book entry.
Receipt — seller to buyer as evidence of payment received.

Only steps 3 and 5 generate primary ledger entries. Steps 1, 2, 4 and 6 are part of the audit trail but do not by themselves trigger a book-of-original-entry record.

Steps that trigger entries: invoice and payment evidence.
Other documents are reconciliation/verification trails.
Memorise this sequence — it's a frequent 4–6 mark exam item.

Documents and internal control — the A* link

Documents are not just records — they are controls that prevent fraud.

Why must source documents be retained?

Audit trail — the auditor can trace from financial statement back to evidence.
Fraud deterrent — entries without supporting documents are easy to flag.
Tax authorities — require documents to substantiate income, expenses and VAT.
Dispute resolution — invoices and credit notes resolve disagreements with customers and suppliers.
Legal evidence — invoices are admissible evidence of a debt in civil court proceedings.

Internal control implications:

Sequential numbering of invoices and credit notes prevents missing or duplicate entries.
Separation of duties: the person ordering should not be the person approving payment.
Authorisation signatures on petty cash vouchers and orders.

How it’s examined

Paper 1: Direct identification ("Name the source document for…") for 1–4 marks; calculation of trade vs cash discount (3–5 marks); explain the purpose of a specific document (4 marks).

Paper 2: Often embedded — students must identify the document underlying a journal entry or correct treatment of a discount.

Common stems: 'State the source document used to record…', 'Calculate the invoice total…', 'Distinguish between trade discount and cash discount', 'Describe the documents involved from order to settlement'.

Sources: Pearson Edexcel International GCSE in Accounting (4AC1) Specification — Issue 3 (2026 onwards); Edexcel 4AC1 Examiner Reports (2022–2024). Last reviewed 2026-05-19.

Master this Topic

Worked examples, formulae, definitions and the mistakes examiners flag — everything you need to push from a pass to an A*.

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Step-by-step worked examples — Business documentation

Step-by-step solutions to past-paper-style questions on business documentation, written exactly the way a tutor would explain them at the board.

1Identify the correct source document
Getting started• Edexcel 4AC1 style — short-answer (4 marks)• AO1, source-documents
Question
State the source document used to record each of the following transactions: (a) Goods sold on credit to a customer. (b) Goods returned by a customer. (c) A monthly summary sent to a credit customer showing all transactions. (d) A small office expense paid in cash from petty cash.
Step-by-step solution
1. Step 1
  Map each transaction to the document that ORIGINATES it — not the book where it ends up.
Answer
(a) Sales invoice — issued by the seller to the credit customer.

(b) Credit note — issued by the seller to reduce the customer's debt.

(c) Statement of account — a monthly summary of invoices, credit notes, payments and the balance owed.

(d) Petty cash voucher — supports the petty cash payment.
Examiner tip
Examiner reports flag that students often confuse 'credit note' (which reduces debt due to a return or error) with 'debit note' (which CUSTOMER may send to request a credit note, OR seller sends to increase debt). Credit note is the one that adjusts the books.
2Calculate the invoice total with trade and cash discount
Building confidence• Edexcel 4AC1 style — calculation (5 marks)• discounts, AO1, AO2
Question
Sara sells 100 units of Product X at a list price of £50 per unit. Her terms are: 20% trade discount and 2.5% cash discount for payment within 10 days. The customer paid within 7 days. Calculate (a) the invoice total, (b) the cash discount, (c) the amount actually paid.
Step-by-step solution
1. Step 1
  Trade discount is deducted on the invoice — it is the basis of the invoice total. It is NOT recorded in the books.
  $Invoice total = (100 × £50) × (1 − 0.20)$
2. Step 2
  Cash discount is calculated on the invoice total (i.e., after trade discount) and is recorded only when payment is received within the qualifying period.
  $Cash discount = £4,000 × 2.5%$
3. Step 3
  Amount paid = Invoice total − Cash discount taken.
Answer
(a) Invoice total = 100 × £50 × 0.80 = £4,000

(b) Cash discount = £4,000 × 0.025 = £100

(c) Amount paid = £4,000 − £100 = £3,900
Examiner tip
The most-marked error is calculating cash discount on the list price (£5,000) instead of the invoice total (£4,000). Cash discount is always after trade discount.
3Trace the document trail of a credit purchase
Higher• Edexcel 4AC1 style — explain (6 marks)• document-trail, AO1, AO2
Question
Aisha's business orders £3,000 of goods from a supplier on credit. Describe, in order, the source documents involved from order to settlement of the debt.
Step-by-step solution
1. Step 1
  Walk forward through the lifecycle: order → delivery → invoicing → payment.
2. Step 2
  Match each stage to the document that evidences it AND the book(s) it triggers an entry in.
Answer
Purchase order — sent by Aisha to the supplier listing the goods required. (Not a book-of-original-entry source — it triggers no accounting entry.)

Delivery note — accompanies the goods on delivery, signed by Aisha to confirm receipt. (Not a book-of-original-entry source — but used to verify the invoice.)

Purchase invoice — the supplier's demand for payment. Source document for the Purchases Day Book → posted to Purchases (Dr) and supplier's account in the Purchases Ledger (Cr).

Statement of account — supplier's monthly summary showing the outstanding balance. (Not a book-of-original-entry source — used to reconcile.)

Cheque counterfoil / remittance advice / bank-transfer receipt — evidence of payment. Source document for the Cash Book → Dr supplier's account in the Purchases Ledger, Cr Bank.
Examiner tip
A* answers note that only invoices, credit notes, cheque counterfoils and cash receipts are the books-of-original-entry source documents. Orders, delivery notes and statements are evidence but do not directly trigger ledger entries.
4Issue the correct document to correct an over-charge
Higher• Edexcel 4AC1 style — apply (4 marks)• credit-note, AO1, AO2
Question
A supplier discovers that an invoice issued to a customer overcharged the customer by £150. Explain which document the supplier should now issue, the entries the supplier should make, and the entries the customer should make.
Step-by-step solution
1. Step 1
  An overcharge reduces the customer's debt — the document that reduces a debt is a credit note.
2. Step 2
  Apply the double entry. Seller: reduce Sales/Returns and reduce Receivable. Buyer: reduce Purchases and reduce Payable.
Answer
The supplier issues a credit note to the customer for £150.

Supplier's books:

Dr Sales Returns / Returns Inwards £150 (or directly Dr Sales £150 if treated as an invoicing correction)

Cr Customer (Sales Ledger) £150 (Reduces the customer's debt by £150.)

Customer's books:

Dr Supplier (Purchases Ledger) £150

Cr Returns Outwards / Purchases Returns £150 (Reduces the customer's amount owed to the supplier by £150.)
Examiner tip
Note: an overcharge is treated like a return for entry purposes — debits and credits mirror those for goods returned. Many students mistakenly issue a 'debit note' from the supplier (wrong direction).
5State who issues and who receives each document
Getting started• Edexcel 4AC1 style — short-answer (4 marks)• documents, AO1
Question
For each document, state who ISSUES it and who RECEIVES it: (a) Sales invoice (b) Credit note (sales return) (c) Statement of account (d) Receipt for cash payment
Step-by-step solution
1. Step 1
  Trace each document from issuer (the party that produces it) to recipient (the party that uses it).
Answer
(a) Issued by seller → received by buyer.

(b) Issued by seller → received by buyer (after goods returned).

(c) Issued by seller → received by buyer (monthly summary).

(d) Issued by seller (who received the cash) → received by buyer (the payer).
Examiner tip
Don't confuse 'who PAYS' with 'who ISSUES the document'. The seller pays nothing on a sales invoice but is the one issuing it.
6Identify whether each item is a primary source document
Building confidence• Edexcel 4AC1 style — short-answer (4 marks)• source-documents, AO1, AO2
Question
State whether each is a PRIMARY source document for the books of original entry, or NOT a primary source: (a) Purchase order (b) Sales invoice (c) Bank statement (d) Petty cash voucher
Step-by-step solution
1. Step 1
  Primary source = directly triggers a book-of-original-entry record. Reconciliation documents and pre-invoice paperwork are not primary sources.
Answer
(a) NOT a primary source — order is a pre-invoice document; no ledger entry until the invoice arrives.

(b) PRIMARY source — drives the Sales / Purchases Day Book.

(c) NOT a primary source — the bank's record; used to RECONCILE the Cash Book.

(d) PRIMARY source — drives the Petty Cash Book.
Examiner tip
Bank statement is the classic trick. It feels like a source — but the BUSINESS's record (Cash Book) is the source; the bank statement is used to check it.
7Calculate the invoice total — trade discount only
Getting started• Edexcel 4AC1 style — calculation (3 marks)• trade-discount, AO1, AO2
Question
A supplier sells 50 units at a list price of £80 per unit. A trade discount of 15% is given. Calculate the invoice total.
Step-by-step solution
1. Step 1
  Invoice Total = List Price × (1 − Trade Discount %)
Answer
List price = 50 × £80 = £4,000. Invoice Total = £4,000 × (1 − 0.15) = £4,000 × 0.85 = £3,400
Examiner tip
Bare 3-marker — show the working line, the formula application, and the answer with currency unit.
8Calculate the cash discount and amount paid
Building confidence• Edexcel 4AC1 style — calculation (4 marks)• cash-discount, AO1, AO2
Question
An invoice of £2,400 offers a 2% cash discount for payment within 7 days. The customer pays within 5 days. Calculate (a) the cash discount and (b) the amount actually paid.
Step-by-step solution
1. Step 1
  Cash discount is taken because payment is within the qualifying period.
Answer
(a) Cash discount = £2,400 × 2% = £48.

(b) Amount paid = £2,400 − £48 = £2,352.

Recording (seller's view): Dr Bank £2,352, Dr Discount Allowed £48, Cr Customer £2,400.
Examiner tip
A* candidates add the journal-style summary — shows complete bookkeeping awareness for an extra method-credit mark.
9Calculate trade discount, cash discount and net cash settlement
Higher• Edexcel 4AC1 style — calculation (6 marks)• sequence, AO1, AO2
Question
A wholesaler sells 200 units at a list price of £30 per unit. Trade discount is 25%. Cash discount is 3% for payment within 10 days. The customer pays in 8 days. Calculate (a) the invoice total, (b) the cash discount, (c) the net amount received in the bank.
Step-by-step solution
1. Step 1
  Sequence: list price → less trade discount → invoice total → less cash discount (if taken) → net amount.
Answer
(a) Invoice total: List price = 200 × £30 = £6,000 Invoice Total = £6,000 × (1 − 0.25) = £4,500

(b) Cash discount: = £4,500 × 3% = £135

(c) Net amount received: = £4,500 − £135 = £4,365

A* check: trade discount is NEVER applied to the £6,000 + cash discount; the calculation is strictly sequential.
Examiner tip
Most-marked error: calculating cash discount on the £6,000 list price (would give £180). Always discount AFTER trade discount.
10Identify the documents needed to resolve an over-delivery
Higher• Edexcel 4AC1 style — short-answer (4 marks)• document-trail, AO1, AO2
Question
A supplier delivers 50 units instead of the 30 ordered. The customer keeps 30 units and returns 20. Describe the documents that should now be issued and the entries that follow.
Step-by-step solution
1. Step 1
  Trace the original transaction and the correcting action.
Answer
Original sales invoice for 50 units — recorded at the over-delivered quantity by the seller (Sales Day Book) and buyer (Purchases Day Book).

Delivery note signed for 30 + 20 returned.

Credit note issued by the seller for the 20 returned units. Recorded in the Sales Returns Day Book (seller) and Purchases Returns Day Book (buyer).

Updated statement of account at month-end reflecting the credit note.
Examiner tip
Document trails like this often test whether students can think sequentially through a transaction. A* answers spell out which book of original entry each document feeds.

Key Formulae — Business documentation

The formulae you need to memorise for business documentation on the Pearson Edexcel IGCSE 4AC1 paper, with every variable defined in plain English and a note on when to use it.

Trade discount calculation
$Invoice Total = List Price × (1 − Trade Discount %)$
$List Price$
The published or catalogue price before any discount
$Trade Discount %$
Bulk-buy or trade-partner discount; deducted on the invoice and NOT recorded in the books
When to use
Whenever a supplier offers a percentage trade discount. The result is the figure that appears on the invoice and in the books.
Example
100 units × £50 list × (1 − 0.20) = £4,000 invoice total.
Cash discount (settlement discount)
$Cash Discount = Invoice Total × Cash Discount %$
$Invoice Total$
The amount after any trade discount
$Cash Discount %$
Discount offered for early settlement (e.g., 2.5% if paid within 10 days)
When to use
Only when the customer pays within the specified period. Recorded in the discount columns of the three-column Cash Book — posted to Discount Allowed (seller) or Discount Received (buyer).
Example
£4,000 invoice × 2.5% = £100 cash discount.
Amount actually paid after settlement discount
$Amount Paid = Invoice Total − Cash Discount Taken$
$Invoice Total$
Amount after trade discount
$Cash Discount Taken$
Cash discount only if payment is within the qualifying period
When to use
When settling an invoice within the cash-discount window.
Example
£4,000 − £100 = £3,900 paid by cheque.

Key Definitions and Keywords — Business documentation

Definitions to memorise and the exact keywords mark schemes credit for business documentation answers — sharpened from recent examiner reports for the 2026 Pearson Edexcel IGCSE 4AC1 sitting.

Source document
Examiner keyword
The original written evidence of a transaction (e.g., invoice, receipt, cheque counterfoil) that forms the basis for entries in the books of original entry.
Sales invoice
Examiner keyword
A document issued by the seller to the customer listing the goods/services supplied, quantities, prices, trade discount and total amount owed.
Purchase invoice
The same document as a sales invoice, but viewed from the buyer's perspective — the seller's invoice received by the buyer.
Credit note
Examiner keyword
A document issued by the seller to the customer to reduce the amount the customer owes — typically because of goods returned, an overcharge, or damaged goods. Source of the Sales Returns / Purchases Returns Day Books.
Debit note
A document issued by the buyer to the seller requesting a credit note (e.g., when the buyer returns faulty goods). Less common as a source document — the seller's credit note is what drives the books.
Statement of account
Examiner keyword
A monthly summary sent by the seller to the credit customer showing opening balance, invoices issued, credit notes issued, payments received and closing balance.
Trade discount
Examiner keyword
A reduction in the list price given to encourage bulk buying or for trade-partner status. Deducted on the invoice and NOT recorded in the accounting books.
Cash discount (settlement discount)
Examiner keyword
A reduction allowed for early settlement of a debt. IS recorded as Discount Allowed (income for the seller is reduced; treated as an expense in the seller's books) or Discount Received (an income for the buyer).
Cheque counterfoil
The stub remaining in the cheque book after writing a cheque — used as evidence of bank payments when posting to the Cash Book.
Paying-in slip
A document completed when depositing cash or cheques at the bank; the stub is retained as evidence of the deposit.
Receipt
Written evidence that a payment has been received by the seller. Used as the source for cash receipts in the Cash Book.
Petty cash voucher
A document authorising a small cash payment from the petty cash float, listing the amount, purpose, date and signatures. Source for entries in the Petty Cash Book.
Bank statement
A periodic statement issued by the bank listing all transactions on the business's bank account. Used for bank reconciliation (Topic 3), not as a primary source document for the Cash Book.

Common Mistakes and Misconceptions — Business documentation

The traps other students keep falling into on business documentation questions — taken from recent Pearson Edexcel IGCSE 4AC1 examiner reports and mark schemes — and how to avoid them.

✕Recording trade discount as a separate entry in the books.
Edexcel 4AC1 examiner reports flag this annually.
Why it happens
Students see a percentage discount and reach for a 'Discount Allowed' or 'Discount Received' entry by reflex.
How to avoid it
Trade discount is part of the price negotiation — it never enters the books. Only the net invoice figure is recorded. Memorise: 'Trade discount = invoice prep. Cash discount = ledger entry.'
✕Calculating cash discount on the list price rather than on the invoice total (after trade discount).
Why it happens
Sequence error — students apply both percentages independently to the list price.
How to avoid it
Always apply trade discount FIRST to get the invoice total, THEN apply cash discount to that figure.
✕Confusing credit notes (issued by seller) and debit notes (sent by buyer).
Why it happens
Both adjust trade balances; the names sound similar.
How to avoid it
Credit note = the SELLER issues it to CREDIT the customer's account (reduce the debt). Debit note = the BUYER may send to request a credit note. The credit note is the one that drives the books.
✕Treating a purchase order or delivery note as the source document for the Purchases Day Book.
Why it happens
These documents precede the invoice and feel 'first'.
How to avoid it
Purchases Day Book is triggered by the invoice — the demand for payment. Orders and delivery notes are evidence trails but do not result in a ledger entry.
✕Using the bank statement as the primary source for the Cash Book.
Why it happens
It's the most complete record of bank activity.
How to avoid it
The Cash Book is the business's OWN record, written from cheque counterfoils, paying-in slips and remittance advices. The bank statement is the BANK's record — used afterwards to RECONCILE the Cash Book (Topic 3).
✕Treating a statement of account as a source document for an entry.
Why it happens
It is a formal document sent by the seller.
How to avoid it
A statement of account is a summary of transactions already recorded. It does not generate new entries — it is used to reconcile the customer's records with the supplier's.
✕Forgetting that VAT is calculated AFTER trade discount but BEFORE cash discount.
Why it happens
Three-step pricing is complex under time pressure.
How to avoid it
Standard UK order: List price → less trade discount → add VAT → invoice total. Cash discount, if taken, is then deducted from the invoice total at settlement.

Practice questions

Exam-style questions with step-by-step worked solutions. Try one before checking the method.

Past paper style quiz

Get a report showing which sub-topics you've nailed and which ones still need work.

Business documentation

Short Study Notes in the form of Slides

Short Study Notes — Business documentation

Detailed Notes

What you’ll learn

How it’s examined

1Identify the correct source document

2Calculate the invoice total with trade and cash discount

3Trace the document trail of a credit purchase

4Issue the correct document to correct an over-charge

5State who issues and who receives each document

6Identify whether each item is a primary source document

7Calculate the invoice total — trade discount only

8Calculate the cash discount and amount paid

9Calculate trade discount, cash discount and net cash settlement

10Identify the documents needed to resolve an over-delivery

Trade discount calculation

Cash discount (settlement discount)

Amount actually paid after settlement discount

Source document

Sales invoice

Purchase invoice

Credit note

Debit note

Statement of account

Trade discount

Cash discount (settlement discount)

Cheque counterfoil

Paying-in slip

Receipt

Petty cash voucher

Bank statement

✕Recording trade discount as a separate entry in the books.

✕Calculating cash discount on the list price rather than on the invoice total (after trade discount).

✕Confusing credit notes (issued by seller) and debit notes (sent by buyer).

✕Treating a purchase order or delivery note as the source document for the Purchases Day Book.

✕Using the bank statement as the primary source for the Cash Book.

✕Treating a statement of account as a source document for an entry.

✕Forgetting that VAT is calculated AFTER trade discount but BEFORE cash discount.

Practice questions

Past paper style quiz

Assess your understanding