What a route actually is

A route answers one question: when this product is needed, where does it come from?

Three answers are possible.

Buy — raise a purchase order to a supplier.

Manufacture — create a manufacturing order to make it.

Replenish on Order — do not act until something actually demands it.

Every product carries one or more of these, set on its Inventory tab. Get them wrong and the system either does nothing when you expected it to act, or acts when you did not want it to.

Buy

The simplest. When this product is needed, purchase it.

Set this on: raw materials, components, and anything you resell without changing.

What it needs: a supplier on the product, with a price and a lead time. Without a supplier, Odoo knows it should buy but not from whom.

Manufacture

When this product is needed, make it.

Set this on: anything you produce or assemble.

What it needs: a bill of materials. Route and BoM work together — the route says make it, the BoM says how.

A very common setup error: a product with a BoM but without the Manufacture route ticked. The recipe exists and nothing uses it. Manufacturing orders are not created, and sales orders do not trigger production.

If manufacturing is not happening when you expect it to, check the route first.

Replenish on Order

This one is different from the other two, and it is the one people misunderstand.

It does not say where the product comes from. It says when to act: only when there is actual demand.

It is always used together with Buy or Manufacture.

Manufacture + Replenish on Order — a sales order for this product creates a manufacturing order. You make to order.

Buy + Replenish on Order — a sales order creates a purchase order. Sometimes called drop-ship behaviour, depending on your setup.

Without it, the product is made or bought to stock, and reordering rules govern when.

Make to stock or make to order

This is the underlying choice, and it is a business decision rather than a technical one.

Make to stock. You produce or buy ahead of demand and hold inventory. The customer gets it quickly. You carry the stock and the cash tied up in it.

Make to order. Nothing happens until an order arrives. No stock held, no obsolescence risk. The customer waits.

Neither is right in general. Fast-moving standard products usually want stock. Configured, expensive or perishable products usually want order-driven.

Most businesses use both, product by product.

How it plays out

Three worked examples make this concrete.

A standard product held in stock

Route: Manufacture. Reordering rule: minimum 50, maximum 200.

Stock falls below 50. A manufacturing order is created automatically. You produce to 200. A customer order ships from stock immediately.

A made-to-order product

Route: Manufacture + Replenish on Order. No reordering rule.

Nothing happens until an order arrives. Confirming the sales order creates the manufacturing order. The customer waits for your production lead time.

A purchased component

Route: Buy. Reordering rule: minimum 100, maximum 500.

Stock falls below 100. A request for quotation is created for your preferred supplier. You receive, and stock is available for production.

Multi-level products

If you make a product from a sub-assembly that you also make, each level needs its own route.

Finished product: Manufacture. Sub-assembly: Manufacture. Raw components: Buy.

Odoo will chain them — demand for the finished product creates a manufacturing order, which creates demand for the sub-assembly, which creates its own manufacturing order or draws from stock.

Keep the chain short. Deep multi-level setups are hard to trace when something does not happen as expected.

What goes wrong

Five patterns, in order of how often they appear.

No route set at all. The most common. A BoM exists, no Manufacture route, and nothing ever produces. The recipe sits unused.

Manufacture route with no BoM. The mirror problem. Odoo knows to make it and does not know how.

Buy route with no supplier. It knows to purchase and has nobody to purchase from.

Replenish on Order plus a reordering rule. These fight each other. One says act only on demand, the other says keep stock. Pick one.

Wrong route on a component. A purchased component set to Manufacture, or vice versa. Produces confusing chains that are hard to follow.

Checking your setup

Four quick checks.

Every manufactured product has the Manufacture route and a BoM.

Every purchased product has the Buy route and at least one supplier with a price.

Nothing has both Replenish on Order and a reordering rule.

Test one of each. Confirm a sales order for a made-to-order product and check the manufacturing order appears. Drop stock below a minimum and check the order is created.

That last one is the real test. Configuration that looks right and does not fire is common, and you want to find that on a test rather than when a customer is waiting.

The short version

A route answers where a product comes from when it is needed: Buy, Manufacture, or Replenish on Order.

The first two say where from. The third says when — only on actual demand.

The most common problem is a product with a BoM and no Manufacture route. Everything looks configured, and nothing ever happens.

Set routes deliberately per product, decide make-to-stock or make-to-order as a business question, and test that each one actually fires.