Finance & Accounting

Manufacturing & Inventory Accounting: BOMs to COGS

Set up items and BOMs, run work orders through issue → labor → overhead → complete, choose a costing method, read variances, and manage E&O reserves - all on perpetual inventory.

Updated 9 min read1 labOwner / FounderAccountant

Manufacturing accounting in Fintra runs on perpetual inventory: every material issue, labor application, and completion posts a real journal entry, so your WIP and finished-goods balances are always current. This page walks the item → BOM → work order → COGS path and the reserves that keep inventory honest.

Items and bills of materials

Create items with a type (raw material, component, finished good) and a costing method. A BOM ties a finished good to its components - each line a quantity-per with optional scrap percentage - plus labor hours/rate and an overhead rate.

  • Explode a BOM to see the flattened raw-material requirements (to leaves or to direct components).
  • Cost rollup computes the rolled-up standard unit cost = material + labor + overhead.
  • BOMs are versioned per finished good so you can revise without losing history.

Running a work order

The work-order lifecycle

  1. 1

    Create & release

    Create the work order (finished good, quantity, linked BOM) and release it to production.

  2. 2

    Issue materials

    Auto-explode the BOM or add manual lines - posts DR WIP / CR Raw Materials.

  3. 3

    Apply labor & overhead

    Accumulate labor cost and overhead (rate × basis) onto the work order.

  4. 4

    Complete

    Close WIP to finished goods / COGS by the item’s costing method. Selling the good later relieves COGS through perpetual inventory.

Variances and E&O reserves

The manufacturing reports compute material-quantity, labor-rate, labor-efficiency, and overhead variances from a deterministic engine. For aging stock, inventory buckets on-hand by days on shelf.

  • Compute the excess-&-obsolete reserve by aging bucket.
  • True-up the reserve delta to the GL.
  • Scrap obsolete items against the reserve rather than writing them off ad hoc.

Hands-on labs

Practice against a realistic scenario. Each lab lists the steps, what you should see, and the checkpoints that confirm you got the same result.

Lab 1

Build a widget from BOM to finished good

Scenario

Northwind Assemblies makes a control panel from three components. You will create the item and BOM, run one work order, and confirm WIP relieves to finished goods.

Steps

  1. 1

    Create the finished-good item with standard costing and a standard cost.

    Expected: The item appears with costing method = standard.

  2. 2

    Create a BOM with three component lines (qty-per + scrap %) and a labor + overhead rate.

    Expected: Cost rollup shows a unit cost above the raw material total (labor + overhead added).

  3. 3

    Create a work order for 10 units and release it.

    Expected: Status = released.

  4. 4

    Issue materials, apply labor and overhead, then complete.

    Expected: WIP is debited on issue and cleared on completion; finished goods increases by 10 at unit cost.

Checkpoints - you got it right if…

  • The issue posted DR WIP / CR Raw Materials.
  • Completion cleared WIP to finished goods.
  • The variance report shows any standard-vs-actual differences.

Frequently asked questions

Which costing methods are supported?

Weighted-average, standard, and FIFO - set per item. Standard costing surfaces material, labor, and overhead variances; the others derive cost from the perpetual stock ledger.

How does inventory stay accurate without a periodic count?

It is perpetual. Receiving on a PO/bill line posts a stock-ledger entry and a GR-IR accrual; issues, completions, and sales move stock in real time. You still count periodically to validate, and adjustments post to the GL.

What is the E&O reserve for?

Excess and obsolete inventory. Fintra ages on-hand stock by days on shelf, lets you compute a reserve by bucket, trues the delta up to the GL, and scraps obsolete items against the reserve so write-offs are controlled and auditable.

Does selling a finished good relieve COGS automatically?

Yes. A finished-good sale relieves COGS through perpetual inventory using the item’s costing method, so revenue and cost of goods land in the same period.

Previous in Finance & AccountingLeads to Commission: Pipeline, Wins, and PayoutNext in Finance & AccountingProcurement: PO → Receive → 3-Way Match → Pay

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