Build-to-order (BTO) is a production model where a product is assembled only after a specific customer order comes in. The seller stocks the underlying components rather than finished units, then puts them together to match the exact options a buyer selected. It is common for configurable products like computers, machinery, and furniture, where the number of possible variants is too large to keep on the shelf.
How it works
A buyer picks their configuration (processor, finish, dimensions, add-ons). That choice defines a bill of materials, the seller confirms component availability, and assembly starts. Because you hold parts instead of completed goods, you cover a wide catalog of variants without warehousing each one. The trade-off is lead time: the buyer waits for assembly rather than shipping from stock.
Why it matters for B2B quoting
BTO products rarely have a single fixed price. Each configuration changes the component mix, and therefore the cost, the margin, and the delivery date. That is why these products usually move through a quote rather than a standard add-to-cart flow. The buyer specifies what they need, and you respond with a price and lead time built around that exact configuration.
On Shopify, this fits a request-a-quote workflow well. A buyer submits their desired build, you price the specific bill of materials, and you send back a quote they can review and accept. Turning that agreed configuration into a draft order keeps the confirmed spec, price, and terms attached to the eventual purchase, so nothing is re-keyed between the quote and checkout. See the B2B quoting glossary for related terms like configure-to-order and lead time.
Example
A workstation seller stocks CPUs, GPUs, RAM, and cases. A buyer requests 20 units with a specific GPU and 64GB of RAM. The seller prices that build, quotes a two-week lead time, and only orders or assembles once the buyer accepts.