On-Hand vs Available Inventory: Which Number Should You Sell?

Start with the stock states

On-hand usually describes stock physically present or recorded at a location. A reservation sets stock aside for demand. A hold can prevent a damaged or uninspected unit from being sold. Available stock is the quantity your rules permit a customer to order now.

Names and calculations vary between systems. Shopify, for example, distinguishes available, committed, unavailable, incoming, and on-hand states in its inventory documentation. Use that as a reminder to map definitions, not as a universal formula for every platform. Ask what each field includes before connecting it to another system.

Incoming goods need their own treatment. A supplier purchase order is not evidence that the goods arrived, passed receiving, or can meet a customer’s delivery promise. Selling against future receipts is a separate policy that must account for timing and uncertainty.

Work through one SKU

Consider an illustrative item with 20 units on hand. Six units are reserved for open orders, three are held for inspection, and the team keeps a two-unit buffer against delayed channel updates. If those categories are mutually exclusive and your rules deduct all three, nine units remain available to publish: 20 − 6 − 3 − 2.

The important assumption is that the categories do not overlap. If the three held units are already included in another unavailable total, deducting both values understates stock. If the source has already calculated available inventory, subtracting reservations again can create the same error.

Write the calculation in plain language and test it against actual system definitions. Include location ownership: stock at a store that cannot fulfill an online order should not silently become online availability.

Follow the events, not just the balance

When a customer places an order, the system may reserve a unit while physical stock remains unchanged. Shipment later changes the physical quantity and clears the reservation. If a connection treats both events as an additional deduction from the same balance, it can double-count the sale.

A cancellation is equally revealing. Confirm whether work can still be stopped and whether the stock is eligible for release. A refund does not establish that a returned product is present and sellable. Receipt, inspection, and disposition must be resolved before availability increases.

For a transfer, define when the unit leaves the source, whether it is in transit, and when the receiving location accepts it. Without these states, both locations can appear to own the same stock—or neither can explain it.

Check the number at the destination

The quantity sent to a channel and the quantity it accepted may differ. Record rejection, delay, and update ownership. Test a sale during a delayed update, a repeated order message, and a return awaiting inspection. A buffer can reduce exposure to delay, but it also withholds inventory; choose it deliberately and review its effect.

Use a small acceptance worksheet: starting balance, event, expected physical balance, expected reserved balance, expected sellable quantity, and observed destination quantity. The team should be able to explain any difference without editing numbers until they look right.

Bring the stock calculation to a 1XA walkthrough

Evaluate 1XA inventory management with one SKU, two locations, a reservation, and a held return. Confirm supported connections, field ownership, and update timing. Then use the multichannel overselling guide to review the wider channel process.

Next step: Request a focused inventory demo. Bring an anonymized stock-state example and the point where your team loses confidence in the number.