Charts of accounts rarely start messy. They get that way one exception at a time: a new code for a one-off project, a duplicate created by a new bookkeeper, an “Other expenses 2” when the first one filled up. After a few years the profit and loss account has 120 lines, half of them with a handful of transactions, and the same cost appears in three places.
Signs it needs attention
- Several accounts with near-identical names (Phone, Telephone, Mobiles).
- Accounts with no postings for over a year.
- Large balances in “Sundry”, “General expenses” or suspense.
- Management accounts that need manual regrouping every month.
- The accountant re-mapping the trial balance at every year end.
Step 1: export and analyse
Export the trial balance and a transaction count per account for the last 12 to 24 months. Sort by count. Accounts with very few postings are candidates to merge; accounts with very many mixed postings are candidates to split.
Step 2: design the target structure
Group accounts in the order of the statutory formats, with a numbering range for each:
| Range | Group |
|---|---|
| 0000–0999 | fixed assets and depreciation |
| 1000–1999 | current assets: stock, debtors, prepayments, bank |
| 2000–2999 | liabilities: creditors, accruals, VAT, PAYE, loans |
| 3000–3999 | equity: share capital, reserves, retained earnings |
| 4000–4999 | turnover |
| 5000–5999 | cost of sales |
| 6000–8999 | overheads by type |
| 9000–9999 | suspense and system accounts |
Within each group, an account should exist only if someone uses its balance separately: for VAT, for a disclosure in the accounts, for tax (such as client entertaining) or for a management decision. Everything else is a tracking category or cost centre, not a nominal account.
Step 3: map old to new
List every current account and its new home. Common decisions:
| Situation | Decision |
|---|---|
| Two accounts for the same cost | merge into one |
| One account mixing deductible and non-deductible items | split (for example entertaining) |
| Accounts per project or customer | replace with tracking categories |
| Dormant accounts with nil balance | archive |
| Dormant accounts with a balance | investigate, then journal to the right account |
Step 4: move balances at a period end
Make the change at the start of a financial year where possible, so comparatives stay consistent. Transfer balance sheet balances with a dated journal and an explanation. For profit and loss accounts mid-year, either reclassify the year to date or keep old codes open until the year end and then archive them.
Step 5: update everything that points at accounts
Bank feed rules, supplier and customer defaults, payroll journal mappings, e-commerce integrations and VAT code defaults all refer to nominal codes. Update them at the same time, or transactions will keep arriving in archived accounts.
Step 6: keep it clean
Limit who can create accounts, write a one-line definition for each account, and review the chart once a year.
Detailed guides to the accounts most businesses need include VAT control accounts, payroll liabilities, accruals and prepayments, fixed assets and card payment clearing. The full list is in the chart of accounts section, and suspense balances are dealt with in suspense and clearing accounts.