A manufacturer's production stops if a component runs out. Reordering rules are how Odoo keeps components topped up automatically so that does not happen. This piece explains using reordering rules for manufacturing components.
What a reordering rule is
A reordering rule, in Odoo, sets a minimum and a maximum stock level for a product. When stock falls to the minimum, Odoo generates the replenishment needed to bring it back up toward the maximum. The rule automates the watching: instead of someone monitoring stock and reacting when it gets low, Odoo monitors it against the defined levels and acts. For a manufacturing component, the replenishment will be a purchase if the component is bought, or a manufacturing order if the component is itself made.
Why reordering rules suit components
Manufacturing components are a good fit for reordering rules. A component is consumed steadily as production runs, and a manufacturer needs it to be on hand when production needs it. Reordering rules suit exactly this: they keep a component topped up against a defined level, so that, as production consumes it, it is replenished before it runs short. For the many components a manufacturer holds in stock to support production, reordering rules are the practical way to keep them available without constant manual watching.
Setting the levels
Using reordering rules well is mostly about setting the minimum and maximum levels sensibly, and that is a real decision per component.
The minimum is the level at which replenishment is triggered. It has to be high enough that, given the time replenishment takes, the component does not run out before the replenishment arrives. A minimum set too low means stock-outs despite the rule; a minimum set too high means more stock held than necessary.
The maximum determines how much is replenished, how far stock is brought back up. A higher maximum means fewer, larger replenishments and more stock held; a lower maximum means more frequent, smaller replenishments and less stock held.
Setting these well means balancing the risk of a stock-out against the cost of holding stock, and it depends on the component's consumption rate and its replenishment lead time. A manufacturer should set the levels deliberately, from those realities, not by guesswork.
Lead time matters
The lead time of a component, how long replenishment takes, is central to setting the minimum. If a component takes a long time to replenish, the minimum has to be set higher, so there is enough stock to last through that lead time after the rule triggers. If it replenishes quickly, the minimum can be lower. Reordering rules and lead times work together: the rule triggers at the minimum, and the lead time determines how much buffer the minimum needs to provide. Accurate lead times are part of making reordering rules reliable.
Reordering rules and MRP together
Reordering rules are one way to keep components supplied; planning driven by MRP is another. The two are complementary. Reordering rules suit components consumed steadily, keeping them topped up against levels. MRP-driven planning works from specific demand exploded through BOMs. A manufacturer typically uses both: some components managed by reordering rules, some pulled by demand-driven planning, according to what suits each. The choice for a given component is part of setting up the manufacturer's planning sensibly.
Review the levels
One honest note. Reordering rule levels are not set once and forgotten. As consumption changes, as a product's demand rises or falls, as lead times change, the right minimum and maximum change too. A manufacturer should review its reordering rule levels periodically, so they continue to reflect reality. Levels set a year ago against a different consumption rate may now be causing either stock-outs or excess.
The takeaway
Reordering rules in Odoo keep manufacturing components topped up automatically by setting a minimum level that triggers replenishment and a maximum that determines how much. They suit components consumed steadily. Setting the levels well means balancing stock-out risk against holding cost, accounting for the component's consumption rate and lead time, and reviewing the levels as reality changes. Reordering rules and MRP-driven planning are complementary. For how we approach Odoo for manufacturers, see our manufacturing work.