Module 3 — Posting to the ledger and the trial balance
Level: Beginner · Duration: 4 hours · Tracks: 🔵 🟣 · Prerequisite: Module 2
1. Objectives
By the end of this module you will be able to:
- Post journal entries to ledger accounts and extract the balance of each account.
- Build a balanced trial balance from scratch.
- Diagnose why a trial balance does not balance using four systematic checking techniques instead of hunting at random.
- Recognise the errors a trial balance does not catch, and why balancing is not proof of correctness.
- Match the bank account balance in your books against the bank statement (bank reconciliation).
2. Core concepts
2.1 Why post at all?
The journal is ordered by time: it tells you what happened on 8 January. But it does not answer a simple question: what is the bank balance right now? To answer it you have to gather all the scattered bank entries into one place. That is the ledger: the same data, ordered by account instead of by time.
Journal (by date) ──post──▶ Ledger (by account) ──total──▶ Trial balance
2.2 The shape of a ledger account
| Date | Ref | Description | Debit | Credit | Balance |
|---|---|---|---|---|---|
| 1/1 | J-001 | Capital | 150,000.00 | 150,000.00 | |
| 1/1 | J-002 | Founder's loan | 50,000.00 | 200,000.00 | |
| 5/1 | J-004 | Shipping and customs | 9,000.00 | 191,000.00 |
The "Balance" column is cumulative. For an account that is debit by nature (like the bank): balance = previous + debit − credit. For credit-natured accounts, the reverse.
2.3 A complete ledger account — Bank (1010) for January
| # | Description | Debit | Credit | Balance |
|---|---|---|---|---|
| J-001 | Capital | 150,000.00 | 150,000.00 | |
| J-002 | Founder's loan | 50,000.00 | 200,000.00 | |
| J-004 | Shipping and customs | 9,000.00 | 191,000.00 | |
| J-005 | Prepaid rent + its tax | 18,900.00 | 172,100.00 | |
| J-006 | Equipment + its tax | 25,200.00 | 146,900.00 | |
| J-007 | Software + its tax | 1,260.00 | 145,640.00 | |
| J-011 | Payment gateway settlement | 76,893.60 | 222,533.60 | |
| J-012 | Delivery company settlement | 19,320.00 | 241,853.60 | |
| J-013 | Advertising | 15,000.00 | 226,853.60 | |
| J-014 | Salaries | 12,000.00 | 214,853.60 | |
| J-015 | Payment to supplier | 30,000.00 | 184,853.60 | |
| Balance at 31 January | 184,853.60 debit |
2.4 The trial balance
A list of every account and its balance on a given date, in two columns: debit balances and credit balances. If the two totals do not match there is certainly an error.
2.5 What the trial balance does not catch — four errors that pass through untouched
| The error | An example from a store | Why it still balances |
|---|---|---|
| Complete omission | You forgot the advertising invoice entry entirely | Neither of its two sides was recorded |
| Wrong account | You booked Amazon's fees under "Payment gateway fees" | The amount and the direction are both right |
| Wrong amount on both sides | You wrote 8,700 instead of 7,800 on both sides | They are equal even though they are wrong |
| Duplicated entry | You posted the gateway statement twice | Each copy balances on its own |
The point: balancing is a necessary condition, not a sufficient one. The real guarantee is matching against an external document: the bank statement, the gateway statement, the physical stock count.
2.6 Diagnosing an out-of-balance trial balance — four techniques, in order
| # | The technique | When it applies |
|---|---|---|
| 1 | Difference ÷ 2 | If you find an amount equal to half the difference, an entry was put on the wrong side |
| 2 | Difference ÷ 9 | If the difference divides by 9 with no remainder, it is most likely transposed digits (5,940 instead of 5,490) |
| 3 | Difference is a round number | 1,000 or 10,000 ⇒ an error in the number of zeros |
| 4 | Top-down check | Work back from the trial balance → the ledger → the journal → the document, comparing the totals at each layer |
3. A worked example — Nuwa's trial balance at 31 January 2026
After posting every entry (including cost of goods sold and the adjusting entries you will master in Modules 4 and 6):
| Code | Account | Debit | Credit |
|---|---|---|---|
| 1010 | Bank | 184,853.60 | |
| 1110 | Due from payment gateway | 0.00 | |
| 1120 | Due from delivery company | 0.00 | |
| 1200 | Inventory | 35,880.00 | |
| 1300 | Prepaid expenses | 15,000.00 | |
| 1400 | VAT — Input | 6,104.40 | |
| 1500 | Equipment | 24,000.00 | |
| 1510 | Accumulated depreciation — equipment | 500.00 | |
| 2010 | Suppliers | 30,000.00 | |
| 2020 | Accrued expenses | 2,500.00 | |
| 2100 | VAT — Output | 8,526.00 | |
| 2200 | Related-party loan | 50,000.00 | |
| 3010 | Paid-in capital | 150,000.00 | |
| 4010 | Sales | 99,500.00 | |
| 4020 | Sales returns | 3,980.00 | |
| 5010 | Cost of goods sold | 33,120.00 | |
| 6010 | Payment gateway fees | 2,388.00 | |
| 6020 | Delivery costs | 1,500.00 | |
| 6110 | Marketing and advertising | 15,000.00 | |
| 6210 | Salaries and wages | 12,000.00 | |
| 6220 | Rent | 3,000.00 | |
| 6230 | Software and subscriptions | 1,200.00 | |
| 6240 | Professional fees | 2,500.00 | |
| 6300 | Depreciation expense | 500.00 | |
| Total | 341,026.00 | 341,026.00 |
A quick read of the trial balance before moving to the statements:
- The balances of 1110 and 1120 are zero ⇒ the gateway and the delivery company settled everything they owed inside the month. Had a balance remained, it would be your money still in transit and it would have to appear on the balance sheet.
- 1400 and 2100 are not offset against each other in the books day to day, only when the return is prepared: 8,526.00 − 6,104.40 = 2,421.60 due to the Authority.
- Inventory 35,880 ÷ 69 = 520 units — match that against the physical count, because the trial balance has no idea whether a unit was stolen.
4. Exercises
E3.1 — Posting (beginner). Draw the ledger account for each of: 1200 Inventory, 2010 Suppliers, 1400 Input VAT, extracting the balance of each at 31 January. Check: inventory 35,880 · suppliers 30,000 credit · input tax 6,104.40.
E3.2 — Extracting the balance (beginner). The "Due from payment gateway" account: 83,580 debit and 83,580 credit. What is its balance? What does that mean economically? And what would it have meant if the balance were 12,400 debit?
E3.3 — The trial balance that will not balance (intermediate). A trial balance has debits totalling 268,400 and credits totalling 270,200.
(a) What is the difference? (b) Apply the four techniques in order and say which cause you consider most likely. (c) Propose one specific checking step to carry out first.
E3.4 — Bank reconciliation (intermediate). The bank balance in your books is 184,853.60, and on the bank statement it is 187,113.60. The differences: a cheque issued to the supplier for 3,000 that has not been cashed yet, and bank charges of 740 not recorded in your books. Prepare a bank reconciliation statement and write the correcting entry required.
E3.5 — Silent errors (intermediate→advanced). For each case, does the trial balance go out of balance? And how would you detect it if it does not?
(a) You booked the Amazon commission under "Payment gateway fees" — (b) you posted January sales twice — (c) you wrote 3,890 instead of 3,980 on the debit side only — (d) you forgot the returns entry entirely — (e) you recorded the equipment purchase as 24,000 debit and 24,000 credit, but under "Equipment expense" instead of "Equipment".
5. Mini project — "From the journal to the trial balance"
Deliverable: a ledger sheet and a trial balance sheet, both linked automatically to the journal sheet.
What is required:
- Build an automated ledger sheet: a
SUMIFformula that pulls each account's balance from the journal sheet with no manual copying. - Build a trial balance sheet that reads from the ledger and puts each balance in the correct column automatically, according to its nature.
- Add a "balance check" cell that shows
Balanced ✓or the difference in red. - Test how robust your model is: deliberately introduce one error (flip an amount between debit and credit), confirm the cell caught it, then fix it.
- Write a paragraph: which error will your model never catch, however accurate it is? And what human procedure makes up for that?
Acceptance criteria:
- [ ] The trial balance balances at 341,026.00 on each side.
- [ ] Not one cell is typed by hand in the ledger and trial balance sheets — they are all formulas.
- [ ] The bank balance of 184,853.60 and the inventory of 35,880.00 both match.
- [ ] The deliberate-error test is documented with a before/after screenshot.
- [ ] The paragraph explicitly names at least one of the four kinds of silent error.
6. The test
8 questions · pass 6/8.
-
What is the essential difference between the journal and the ledger?Posting adds not a single new figure; it re-sorts the same data from time to account. That is why neither replaces the other: the journal is a complete chronological trail, the ledger is a ready balance for every account.
-
A credit-natured account has a previous balance of 8,000 credit, then 3,500 debit and 1,200 credit are posted to it. What is its balance?For a credit-natured account: balance = previous − debit + credit, that is 8,000 − 3,500 + 1,200 = 5,700 credit. The formula
previous + debit − creditbelongs to debit-natured accounts like the bank, and applying it here gives the wrong 10,300. -
A trial balance is out by 810. Which technique should you start with?A difference that divides by 9 with no remainder is the signature of transposed digits, and it narrows the hunt to a single amount within minutes. The top-down check is sound but it is technique four: you reach for it after the quick tests fail, not before.
-
Which pair of errors passes through the trial balance without knocking it out of balance?The trial balance survives any error that keeps total debits equal to total credits, and breaks on any error that touches one side only. So balancing is a necessary condition and not a sufficient one, and the real guarantee is a document from outside your books.
-
Why do we not offset input VAT against output VAT in the day-to-day books?Gross recording keeps every dirham of tax attached to its invoice, which is exactly what any tax inspection asks for. The offset is a single periodic event at return time, not a daily practice.
-
The balance of "Due from payment gateway" at 31 March is 18,900 debit. What does it mean and where does it appear?A debit balance on that account is your money in transit, not new revenue. Compare it with Nuwa's trial balance: 1110 stood at 0.00 on 31 January because the gateway settled everything it owed inside the month.
-
Your trial balance balances, but book inventory is 35,880 and the physical count is 34,500. What entry is required?The difference is 35,880 − 34,500 = 1,380, and the physical count is the authority, not the book. Inventory is written down and the shortfall is charged to cost of goods sold — and this is exactly the kind of silent error that balancing never reveals.
-
What is the correct order for tracing a suspicious figure in the trial balance back to its source?This is the top-down check, technique four: every layer carries the reference of the layer beneath it, and comparing the total at each step confines the error to a single layer instead of a random hunt through the whole book.
Pass mark 6 of 8.
7. Completion standard
| # | The standard | The evidence |
|---|---|---|
| 1 | Three ledger accounts posted by hand with correct balances | E3.1 |
| 2 | An automated trial balance balancing at 341,026.00 | The project file |
| 3 | The deliberate error detected and corrected successfully | Two screenshots |
| 4 | A correct bank reconciliation statement + its correcting entry | E3.4 |
| 5 | Naming at least two silent errors with an alternative detection mechanism for each | Written |
| 6 | Test score ≥ 6/8 | The test sheet |
Mastery level (optional): prepare a real bank reconciliation for your business account for the last complete month. Record how many items on the statement you knew nothing about — that number is an honest measure of the distance between your books and your reality.