Should Products Ordered Together Be Stored Together?

Suppose your order history shows that notebooks and pen packs are frequently bought together, but they are stored several aisles apart. Moving the pens next to the notebooks looks promising. Before rearranging the shelves, though, you want to know whether that move will shorten picking across the rest of your orders too.

Products ordered together are a useful starting point for a warehouse slotting change. The next step is to compare the picking routes with the products in their current and proposed locations.

Look beyond the most frequent pair

In this example, the pen packs might also be ordered with folders, with other stationery, or on their own. Moving them beside the notebooks changes the picking location for all those orders, not just the notebook-and-pen combination.

Look at the complete orders containing the products you plan to move. Which other shelves do those orders visit? If another product must move to make space, include its orders too. This gives you a fuller comparison than counting how often two products appear together.

Optimize the route, not just the shelf positions

Putting two products closer together does not tell you the distance of the whole pick trip. The other items on the order, the start and finish points, and the available paths all affect the trip.

SolvingMaze Warehouse Layout Simulation optimizes pick routes for the orders and shelf assignments you provide. It does not apply a fixed picking pattern to every order. When you change the assignments, it computes routes for the new arrangement.

That lets you compare each arrangement with its own optimized routes, rather than judge a stock move by how it fits an unchanged route. You choose the shelf assignments to test; SolvingMaze calculates the resulting picking distance.

Compare the same orders before moving stock

Choose historical orders from a period that reflects the work you want to improve. Keep the order contents, warehouse layout, and picking settings the same across the comparison, so the change in total distance reflects the different shelf assignments.

1. Run the orders with the current shelf assignments and save the total route length.
2. Prepare another version of the order CSV with your proposed shelf assignments. Include any products displaced by the move, and keep the items and quantities unchanged.
3. Run the simulation again and compare total route length. You can test several proposed moves together as one alternative arrangement.

If the idea came from a promotion or seasonal combination, compare orders from that period as well as ordinary trading. That helps you decide whether the move suits regular picking or a particular sales period.

Choose a move worth making

A shorter total route gives you a reason to consider the move. Then weigh the distance reduction against the work of relocating stock. Does the proposed shelf have enough room? Will the products remain easy to pick and replenish? A small reduction may not justify a large reshuffle; a useful reduction from a straightforward move may be worth acting on.

You do not need to reorganize the whole warehouse around product pairs. Start with a workable change, compare its optimized routes, and use the result to decide whether to move stock.

Want to explore how shelf assignments affect picking routes? Create a free Sandbox Warehouse and try a small example. For comparisons using your own warehouse and historical orders, set up a Production Warehouse.