The Cost That Was Never Work in Progress

This is the article for whoever prepares your accounts, and it used to be the least comfortable one in the manufacturing set. The operational picture — what you can do without a bill of materials — was always defensible and in places genuinely good. The accounting picture underneath it had two specific defects that a manufacturer would meet in their first month. Both have since been fixed, and this article has been rewritten rather than quietly deleted, because how they were wrong is the useful part.

What replaced them is not a manufacturing accounting module. It is narrower and more honest than that: the ledger now keeps part-finished work on the balance sheet where it belongs, and it refuses to hide the difference between what a job consumed and what its output was valued at. That difference is the subject of the second half of this article.

Fixed: material issued to a job is no longer expensed on the way out

The old entry on an approved stock issue was expenses debited, inventory assets credited, with no exception. For a retailer that is broadly right. For a manufacturer it was wrong in a specific way: the material had not been consumed in the sense the accounts claimed. It had been transformed, and it was sitting on the factory floor as part-finished goods you still owned.

There is now a Work in Progress account, and an issue charged to a job debits it instead of expenses. When output is received back into stock against that same job, the receipt credits Work in Progress. Material moves from raw inventory into WIP, stays an asset while it is being worked on, and leaves WIP as finished stock — which is what a manufacturing system is supposed to do.

What that changed at month-end: part-finished production used to be worth nothing on paper, so closing the books mid-run — and a mill or a bakery is always mid-run — understated profit by the full cost of everything on the floor and understated total assets by the same amount. The worst books belonged to the busiest month, which is the least convenient time to be reading your own numbers wrong.

The old distortion scaled with how busy you were. A factory with nothing in progress had accurate books; a factory running flat out had the worst ones.

Fixed: your own output no longer arrives as a debt

Receiving finished goods back onto stock used to post inventory assets debited, accounts payable credited. The debit was right — the goods are an asset. The credit was not: accounts payable is money owed to a supplier, and there was no supplier. You made the goods. It created a payable to nobody that grew with every production receipt, and because it sat inside the same balance as real supplier debt it was invisible — the creditors listing simply stopped agreeing with the invoices you actually held, by the cumulative value of everything you had ever manufactured.

The credit is now derived from where the stock actually came from. A delivery against a purchase order or a procurement request still credits accounts payable, because somebody genuinely is owed. Output received against a job credits Work in Progress, which is the entry that relieves the job. A receipt with neither — found stock, an opening balance, a customer return — credits a separate Inventory Received Clearing account, so the value is visible as its own balance you can journal out rather than buried in what you owe your suppliers.

Note the ordering, because it is deliberate: a supplier document beats a job. Material bought for a job is still a purchase, and it only becomes work in progress later, when somebody issues it from the store.

What is left: the two figures still do not agree, and now you can see it

The remaining problem is not a defect so much as the consequence of having no recipe: the cost going in and the value coming out are computed independently. The issue is valued at the unit cost stamped on the line when the stock left the store — the same figure the job costing report uses, which is a change in itself, because the ledger used to read the item's buying price at approval time and so disagreed with the job report about the cost of the same movement. The receipt, though, is still valued at the finished item's standing buying price, a field on the item master that has nothing to do with this run and is not updated by it.

So the two numbers differ, and the difference stays behind in Work in Progress after the job's output has been received. That residual is not an error and it is not netted away. It is the variance between what a job consumed and what its output was priced at, and the honest thing to do with it is show it: there is a Work in Progress by Job report that lists what each job has taken in, what has come back out, and what is still sitting there — with a view for exactly the jobs whose output has arrived and which still did not clear.

The residual can be negative, and a negative one is the more informative case. It means the output was valued above what the job consumed, and the usual reason is labour: the standing price on the item master reflects a selling-side view that includes work the ledger never capitalised, because time costed to a job still sits in payroll expenses and nothing carries it into inventory value.

How far from correct is this, honestly

The routine that is left

Two of the three standing journals this article used to prescribe are gone, because the postings they corrected no longer happen. What is left is shorter, and it is review rather than correction.

1. Make sure issues are coded to jobs

   This is the whole mechanism. An issue with no job on it is expensed, and no amount of month-end work recovers that as work in progress after the fact. If your storekeeper is issuing against a reason but not a project, fix that before anything else on this list.

2. Read the WIP by Job report at close, and ask about the residuals

   Jobs still carrying value are legitimately in progress. Jobs whose output has been received and which still did not clear are the interesting ones — the report has a view for exactly those. A large negative residual usually means the item master price includes labour the ledger never capitalised; a large positive one usually means scrap, or output received at a price set years ago.

3. Set the finished item's price before the receipt, not after

   The output is valued at the standing price on the item master. That price feeds weighted average cost, which feeds margin on every subsequent sale, so getting it right at the receipt is the difference between one correct number and a quarter of wrong margin reporting.

One thing not to do: do not try to fix the finished-goods valuation by leaving the standing price alone and correcting it in a journal. The standing price feeds weighted average cost, which feeds your margins on every subsequent sale of that item. Get it right on the item master before the receipt, or your gross margin reporting is wrong for reasons that have nothing to do with this.