If you build physical products and you've logged into QuickBooks Online recently, you may have noticed something new sitting next to your inventory items: a choice you can no longer avoid. QuickBooks Online's inventory system, historically a simple in-and-out counter built for resellers, has spent 2026 quietly turning into something closer to a lightweight manufacturing system — complete with a real costing-method decision, bills of materials, and manufacturing orders that track a build from raw materials to finished goods.
For small manufacturers who have been bolting spreadsheets and sticky notes onto QuickBooks Online for years just to approximate what a product actually costs to build, this is a meaningful shift. It's also one that can quietly wreck your margins if you pick the wrong settings without understanding what they do. Here's what actually changed, how the pieces fit together, and how to avoid the mistakes that trip up manufacturers moving into this workflow for the first time.
The Big Change: You Now Choose a Costing Method
For most of QuickBooks Online's history, inventory valuation worked one way behind the scenes, and business owners rarely thought about it. That's no longer true. QuickBooks Online now asks you to choose between two inventory costing methods when you set up inventory tracking:
- First In, First Out (FIFO) — assumes the oldest units in stock are the ones sold or consumed first. The cost of each sale is pulled from your earliest purchase "layers," working forward chronologically.
- Moving Average Cost (MAC) — recalculates a single blended cost for every unit in stock every time you receive new inventory. Instead of tracking dozens of purchase-price layers, every unit on the shelf shares the same current average cost.
The catch that trips people up: this choice is effectively permanent once transactions start posting under it. Switching costing methods mid-stream doesn't just flip a setting — it can force a full inventory revaluation and create a jarring one-time gain or loss on your books. Choose deliberately, ideally before you enter your first bill against an inventory item, not six months into the year when you notice your margins look strange.
How Moving Average Cost Actually Works
The moving average formula is simple in concept, even if it runs continuously in the background:
Moving Average Cost = Total Cost of Inventory on Hand ÷ Total Units on Hand
Every time you receive a purchase order or enter a bill for inventory, QuickBooks Online recalculates this average. If you bought 100 units of raw aluminum at $4.00 and then received another 50 units at $4.60, your new moving average cost becomes:
(100 × $4.00 + 50 × $4.60) ÷ 150 = $4.20 per unit
Every unit currently in stock — old and new — is now valued at $4.20, and every future sale or production draw pulls from that single blended number until the next purchase changes it again.
Why manufacturers tend to like it:
- It smooths out price volatility. If your raw material costs swing with commodity markets, MAC dampens the whiplash in your cost of goods sold instead of letting a single expensive purchase spike your reported margin down for a few weeks.
- It's operationally simpler. You're not tracking which specific purchase "layer" a unit came from — useful when materials are commingled in a bin or tank and there's no real way to know which batch a given unit came from anyway.
- It produces steadier gross margin percentages period over period, which is genuinely useful for pricing decisions and management reporting.
Why it isn't automatically the right choice:
- FIFO more closely mirrors physical reality for manufacturers who genuinely do consume older stock first (common with perishables, temperature-sensitive materials, or anything with a shelf life).
- In a period of rising input costs, FIFO tends to show a higher ending inventory value and higher reported profit than MAC — which matters if you're presenting financials to a lender or investor, or trying to manage taxable income.
- If you ever plan to move to a more capable ERP or ever expect to be audited on a layer-by-layer basis, FIFO's transaction trail is easier for an outside accountant to reconstruct and verify.
The honest answer for most small manufacturers: if your input costs are volatile and your materials are commingled, MAC will save you headaches. If your costs are stable or you need the cleanest possible cost-layer audit trail, stick with FIFO. Model both against a quarter of real purchase and sales data before committing — the difference in reported COGS is rarely huge, but it's rarely zero either.
Manufacturing Orders and Bills of Materials
The second half of the 2026 overhaul is arguably the bigger deal for small manufacturers: QuickBooks Online now supports manufacturing orders built on a proper bill of materials (BOM).
Previously, "building" a finished good in QuickBooks Online out of component parts required workarounds — bundling items, manual journal entries, or third-party inventory apps layered on top just to get a rough sense of what a finished product actually cost to assemble. Now, the workflow looks more like:
- Define a bill of materials on a finished-good item — the exact raw materials, components, and quantities required to build one unit.
- Create a manufacturing order to plan a production run, which checks whether you have enough components on hand and flags shortages before you start.
- Complete the build, which consumes the component inventory, calculates the cost of the finished unit based on its components' costs, and adds the finished goods to inventory at that calculated cost.
If you migrated from QuickBooks Desktop, existing inventory assemblies and BOMs typically carry over — pending build assemblies become "planned" manufacturing orders, and completed ones link back to their original build assembly transactions.
It's worth being clear-eyed about the limits here, too. This is not a full manufacturing execution system: multi-level BOMs (a sub-assembly that's itself built from other components) have limited support, there's no shop-floor scheduling, and work-in-progress valuation is still fairly basic compared to purpose-built manufacturing ERPs. For a business running multiple production lines with complex routings, labor costing, and overhead allocation, this will eventually be outgrown. For a small shop building a handful of SKUs from a short, stable parts list, it's a real upgrade from spreadsheet-and-hope.
The Mistakes That Actually Cost Manufacturers Money
None of this new tooling protects you from the underlying discipline problems that have always plagued manufacturing bookkeeping. The most common ones worth guarding against:
A stale bill of materials. When a component gets substituted on the production floor — a different supplier, a slightly different part — but nobody updates the BOM, every unit built afterward is costed against the wrong inputs. That error compounds silently across every build until someone notices margins have drifted for no obvious reason.
Work-in-progress treated as an afterthought. Partially completed units sitting on the floor mid-build are neither raw material nor finished goods, and their value keeps changing as labor and overhead get applied. Manufacturers who don't track WIP explicitly tend to see profit "teleport" between months — a big production run that starts in one month and finishes in the next can make one period look artificially bad and the next artificially good.
Production posting lagging the shop floor. If a build isn't logged in QuickBooks until days after it physically happened, your on-hand inventory counts and cost calculations are out of sync with reality in the meantime — which matters a lot if you're also trying to run accurate reorder points off those numbers.
Overhead that never makes it into the cost. Direct materials and direct labor are the easy part. Rent, utilities, equipment depreciation, and indirect labor that support production often don't get allocated into unit costs at all, which means your "cost per unit" number looks better than it actually is and your pricing can end up underwater without anyone noticing until cash gets tight.
Getting the Underlying Bookkeeping Right
New QuickBooks Online features can compute a moving average or cost a bill of materials perfectly and it still won't save you if the records feeding those calculations are inconsistent, delayed, or opaque. Manufacturing accounting is unforgiving of sloppy inputs — a wrong receiving date, a misclassified expense, or an unreconciled account ripples through every unit cost calculation downstream of it.
This is exactly the kind of problem that benefits from records you can actually inspect and verify, rather than trusting a black-box calculation you can't audit line by line. Beancount.io offers plain-text accounting that keeps every transaction — including inventory movements and cost adjustments — in a transparent, version-controlled format you can review, diff, and reconcile with the same tools developers already use to track code changes. For a manufacturer trying to keep production costs honest, that kind of auditability is worth more than another dashboard. Get started for free and see what plain-text accounting looks like for a business that actually builds things.
