Mapping fixed assets to general ledger accounts: the three-account rule

Every fixed asset you track touches at least three general ledger accounts: the asset cost account, the accumulated depreciation account, and the depreciation expense account. Getting that mapping right at the point of setup saves reconciliation pain at every month-end close afterward.

Which accounts does each asset need?

For reporting purposes, you assign accounts from the general ledger to the asset record. The three to specify are:

• Asset account: carries the original cost of the item.
• Accumulated depreciation (or amortization) account: a contra-asset account that offsets cost, so the net book value reads correctly on the balance sheet.
• Depreciation or amortization expense account: receives the periodic charge on the income statement.

Choose the account numbers from your chart of accounts. If the list does not show the account you expect, it is probably not flagged as the right account type, so fix that in the chart before mapping the asset.

The mapping matters more than the amounts

The depreciation entry itself is mechanical: debit expense, credit accumulated depreciation. The judgement is in the mapping. If two assets of the same class point to different expense accounts, your income statement splits a single category across lines and the numbers stop matching the supporting schedule.

A consistent mapping gives you a clean tie-out. The fixed asset schedule's cost column should agree to the asset account balance. Its accumulated depreciation column should agree to the contra account. The period's depreciation should agree to the expense account movement. When all three tie, the close is quick.

A worked example

Suppose a client buys office furniture for 6,000, depreciated straight-line over five years with no salvage value. The monthly charge is 100.

• Cost sits in the Furniture and fixtures asset account: 6,000 debit.
• Each month, 100 credits Accumulated depreciation, furniture and fixtures.
• Each month, 100 debits Depreciation expense, office equipment.

After 12 months the balance sheet shows cost of 6,000 less accumulated depreciation of 1,200, a net book value of 4,800. The expense account shows 1,200 for the year. Every figure traces back to the asset schedule.

Policy and jurisdiction change the answer

The account structure is universal, but the depreciation method, useful life, and any tax-specific treatment depend on the jurisdiction and the client's accounting policy. Some jurisdictions allow immediate expensing below a threshold, which can mean the item never enters the fixed asset register at all. Confirm the policy before you map the accounts, not after.

Practical checks before you close

Run these three checks each period:

1. The sum of asset costs on the schedule equals the asset account balance.
2. The sum of accumulated depreciation equals the contra account balance.
3. The period's depreciation on the schedule equals the expense posted.

If any check fails, the usual cause is an entry posted directly to the GL without going through the schedule, or an asset mapped to the wrong account at setup. Fix the mapping first, then the entries, and the tie-out will hold from then on.