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Guide · Buyer's guide

How to write a bill of quantities that gets quoted right

The quality of every offer starts with the quality of the list you send. Here is the line-by-line method we see working — straight from the desk.

6 min read · Updated 2026

Why the BOQ matters more than the supplier

A supplier can only quote what you tell them. The difference between two offers for the same project sometimes reaches thirty to forty percent — because one supplier quoted the exact schedule, standard and material, and the other guessed. On welded line pipe connections especially, there is no "close enough": the fittings, flanges, gaskets and bolts must inter-match or the joint will not be made to code. Your list is the contract between your project and everyone who bids on it.

Start with the project frame

Before the line items, give the reader the frame: project or plant name, the duty line, the relevant code or class (e.g. ANSI/ASME B16.5 Class 600), the quantities of connections involved, and the delivery target and location. This lets suppliers align their material to the same design pressure — and lets you compare like for like.

The anatomy of a line item — remove the guesswork

Each row of the BOQ should say:

Write the line like a sentence: example

Take a vague note and the same line rewritten so a quoting team reads it without a single guess:

ITEM A-14 · Weld neck flange · NPS 8, Class 600, RF · ASME B16.5 · material ASTM A105 · Sch. STD bore · EN 10204 3.1 · 12 pcs · gaskets 4 pcs spiral wound graphite filler, ASME B16.20 · stud bolts A193 Gr. B7 × A194 2H nuts, 5/8" × 3-1/2", 24 sets.

That one line tells the factory everything about price: the standard, the material, the class, the quantities and the bolt set. In practice, the three fields that cause most re-manufacturing are the facing (RF vs FF), the schedule on the bore, and the matching bolt set — which is why we always quote flanges, gaskets and bolts as one set.

Common mistakes that delay quotes

Do you have a list already but no time to clean it into this format? That is exactly the work we do — send us the raw file (Excel, PDF or Word) through the RFQ page and we will structure, review the spec against the standards, and return a consolidated, comparable offer.

Have a Bill of Quantities ready?

Send us your BOQ or equipment list and get competitive offers from verified manufacturers — checked against the technical specifications your project requires.