Set up volume discounts and tiered supplier pricing with cost rules

Who this is for

Purchasing teams whose suppliers offer quantity-based pricing — "$5.00/unit under 1,000, $4.50 at 1,000+" — and who want POs to price themselves correctly instead of relying on someone remembering the price break table.

What a unit-cost rule does

A cost rule of type "Adjust unit cost" holds your negotiated pricing for a vendor. When you add products to a PO for that vendor, the rule resolves the correct unit price for the quantity being ordered — automatically, on every PO.

Tiers — price breaks by quantity (e.g. 1–999 at $5.00, 1,000+ at $4.50).
Effects within a tier — a base price, a percent discount or markup, or a fixed per-unit add-on (useful for per-unit component charges like scoops and labels — see Handling per-item component costs on purchase orders).
Scopes — apply the rule to specific products, supplier SKUs, categories, subcategories, or tags. Leave empty to cover everything from that vendor.

The setting most people miss: combined-quantity tiers

Suppose your label supplier prices all label sizes together: order 10,000 labels total and every size gets the volume price. Set Tier quantity based on to "Combined quantity on order" and the tier lookup uses the sum of all matching lines on the PO — so 4,000 small + 6,000 large labels hits the 10,000 tier. The default ("Line quantity") tiers each line on its own.

Practical examples

Simple volume discount — tiers at 1/500/1,000 units with base prices $5.00/$4.75/$4.50.
Negotiated % off list — one tier, percent discount 12%, scoped to a category.
Component add-on — fixed per-unit +$0.60 scoped to a "scoop-and-label" tag.

Rules also respect supplier constraints like minimum order quantities and order multiples — configure these per supplier SKU (see Configure supplier SKUs, MOQs, and purchase units).

Good to know

Unit-cost rules change the PO line's unit price directly — they don't add a separate fee line. For freight/duty-style charges, use an extra-cost rule instead (Automatically add freight, duty, and handling charges to purchase orders).
POs generated from work orders resolve cost rules too — see What are cost rules on a generated purchase order?.
Without a matching rule, the PO falls back to the supplier SKU's standard price (How to setup Unit cost).

"How do I get PO pricing to update automatically at volume price breaks?"
"Can different SKUs count toward one combined discount tier?"
"Where do I store negotiated supplier pricing?"