Bill of Quantities vs Bill of Materials: What's the Difference?

The two terms get used as if they were interchangeable, and they are not. A Bill of Quantities and a bill of materials answer different questions: one is about how the work is priced, the other about what to buy. They overlap, they come from the same place, and on a real job you often need both. Here is the difference, kept short.

What a Bill of Quantities is

A Bill of Quantities measures the work in a project for tendering and pricing. Every item of work (excavation, concrete, reinforcement, drainage, pavement) is described and quantified under a method of measurement, so contractors price the same scope on the same basis. The unit and the description follow the standard: CESMM4, NRM2, SMM7 or MMHW for UK work. A BoQ line reads as work, "excavate and dispose, 105 m³", not as a shopping list. If you want the full grounding, start with what a Bill of Quantities is.

What a bill of materials is

A bill of materials lists the materials and components needed to build something, with quantities, so they can be ordered and the build planned. It comes from manufacturing, where the bill of materials is the parts list for a product, and the same idea carries into construction procurement. A bill of materials line reads as a thing to buy, "C32/40 concrete, 18 m³" or "T16 reinforcement, 2.4 t", priced by a supplier rather than measured under a contract standard.

Work versus materials

That is the core distinction. A BoQ measures work and is structured for pricing a tender; a bill of materials lists materials and is structured for procurement. The same wall produces both: the BoQ has it as measured concrete, reinforcement, formwork and excavation rows coded to a standard; the material list has it as cubic metres of a concrete grade and tonnes of a bar size to order from a supplier.

They also belong to different people. The BoQ is the quantity surveyor's and estimator's document, used to price and to value. The material list is the buyer's and the site team's, used to order, to book deliveries and to control waste.

The overlap, and how one model gives you both

Here is the part that matters: both fall out of the same measured quantities. Once an assembly is measured, the BoQ is one view of those quantities (priced for tender, coded to the standard) and the material schedule is another (grouped by material, supplier-neutral, ready to order). They are two readings of one measurement, not two separate take-offs.

Disclosure: CivilQuants is our product. It measures a civils assembly once and produces both views from the same computation: the BoQ coded to your chosen standard, and a supplier-neutral material schedule in the project workspace's Procurement tab and as a Procurement_Summary sheet in the Excel export. So the order list does not need a second measure. In civils the material schedule is effectively the bill of materials; for the longer treatment, see a material schedule vs a BoQ. For the tooling side, Bill of Quantities software covers what to look for.

FAQ

What is the difference between a BoQ and a bill of materials? A Bill of Quantities measures the work for tendering and pricing, coded to a method of measurement; a bill of materials lists the materials or components to buy, with quantities, for procurement. One prices the job, the other orders the materials.

Is a bill of materials the same as a material schedule? In civils, effectively yes. The procurement take-off, or material schedule, is the construction equivalent of a manufacturing bill of materials: concrete, reinforcement, fill, pipe and aggregate by quantity, supplier-neutral.

Can one model produce both? Yes. Both come from the same measured quantities. CivilQuants produces the coded BoQ and a material schedule from one computation, so the order list does not need a separate take-off.

Which comes first, the BoQ or the bill of materials? The measure comes first. From the measured quantities you derive the BoQ (priced for tender) and the material schedule (to order). They are two views of one measurement, not two exercises.

Does a bill of materials include labour? Usually not. A bill of materials lists materials and components. Labour, plant and method sit in the BoQ rates and the contractor's build-up, not in the material list.

Try it

See both views from one measure: the manhole calculator renders the bill free to MMHW in the browser, and the full catalogue has five more free assemblies. When you need all four standards, the material schedule on every export and clean Excel, DXF and PDF deliverables, the 7-day pass is £15 on the pricing page.