The moment a spreadsheet stops working: your second warehouse
A single-location business can run stock control out of a spreadsheet for years. Someone counts what's on the shelf, updates a cell, and as long as they're careful, the number stays roughly honest.
The moment a second warehouse opens, that habit stops being a minor inconvenience and starts being a liability.
The question a spreadsheet can't answer fast enough
"Do we have this in stock?" used to mean checking one number. With two warehouses, it means checking two numbers, knowing which one is current, and knowing which one a specific customer's order should actually ship from. A spreadsheet doesn't enforce any of that — it just holds whatever was typed into it last, correct or not.
Inter-warehouse transfers make this worse. A transfer is really two updates that both have to happen — stock leaves one location and arrives at another — and a spreadsheet has no way to guarantee both sides actually got edited. One warehouse looking short and the other looking overstocked is usually not a counting mistake. It's a transfer that only got recorded on one side.
What actually needs to be true
- Stock is tracked per warehouse, not as one combined number. "Total stock" is a sum of real, separate numbers — not the only number that exists.
- A transfer updates both sides in the same action. Not two edits, two people, two spreadsheets that might disagree.
- Nothing can be sold from a warehouse that doesn't have it — a sale has to check the exact location it's shipping from, not a company-wide total that might be sitting in the wrong place.
The real signal to watch for
It's rarely "we need software" that triggers the switch — it's usually a specific bad afternoon: a customer promised stock that turned out to be in the other warehouse, or a transfer that got recorded once and then quietly went stale. That's the moment worth acting on, before it becomes a pattern instead of an incident.
See how warehouse transfers work in IDP, or request a free trial on your own stock data.