Files You Need for a PCB Quote: Gerber, BOM, CPL

1. Define the quotation scope

Start with a sentence describing the deliverable. “Quote 50 bare boards” is different from “Quote 50 assembled boards, including component sourcing.” Specify whether the supplier should provide boards, purchase components, assemble supplied components, or handle a mixture of these activities.

Also distinguish finished units from panels. A request for “50 pieces” is ambiguous when one panel contains several boards. Name the unit being counted, identify any quantity breaks requested, and say whether the required date means dispatch or arrival. See the separate overviews of PCB manufacturing and PCB assembly when defining the scope.

2. Collect the fabrication outputs

Gerber data represents board features such as copper and solder mask. It does not, by itself, guarantee that the quotation includes every material or finish requirement. Ucamco explains that fabrication documentation also covers properties such as material, thickness, and finish; the Gerber Job file can carry this information in machine-readable form. Ucamco: Gerber Job.

Ask the design owner to export the intended revision into a clean folder. Include the applicable copper, mask, legend, outline, and drilling outputs, with an understandable layer map. Identify routing, slots, and special hole requirements explicitly. Supply paste layers when requested for stencil or assembly preparation.

In KiCad, Gerber plotting and drill generation are separate operations. The official manual documents Excellon and Gerber X2 drilling outputs, coordinate origins, units, and options for plated and non-plated holes. Follow the supplier’s export instructions rather than changing unfamiliar settings to make an upload succeed. KiCad PCB Editor: drill files.

Open the exported package in a viewer and compare its outline and overall dimensions with the drawing. A successful export message confirms file creation; it does not confirm that the selected layers represent the intended product.

3. Prepare a purchasing-ready BOM

The bill of materials connects component identities to board reference designators. A supplier’s template may request description, designator, footprint, and part-number information; use that template when available. JLCPCB’s published example illustrates these fields, but its particular import rules should not be generalized to every assembler. JLCPCB: BOM file requirements.

Keep board quantity separate from component quantity. If one board uses two identical resistors at R1 and R2, the per-board quantity is two. A request for 50 assembled boards has a nominal demand of 100 of that part. Additional material allowance, packaging, and minimum purchases need separate agreement.

Altium’s documentation distinguishes item quantity, production quantity, and supplier order quantity, and supports BOM output for a selected design variant. Confirm the exported variant before sharing the file. Altium: preparing a BOM.

Define “do not populate” (DNP) clearly. Ask the assembler how its import process handles DNP rows, then preserve a human-readable record of the intended omissions. For substitutions, list approved alternatives or require approval before purchase. Avoid an unrestricted “equivalent parts allowed” note unless that authority has actually been granted.

4. Check the placement file

The component placement list, also called a CPL, centroid, position, or pick-and-place file, connects each component reference to its placement data. As one supplier-specific example, JLCPCB requests reference designators, centroid X and Y coordinates, board side, and rotation; its published convention uses millimeters and positive counterclockwise rotation. Confirm the convention for your actual assembler. JLCPCB: pick-and-place file requirements.

Export from the same board revision and assembly variant used for the BOM. Record the coordinate units and origin, and confirm whether the supplier wants a single-board file or panel data. Follow its instructions for bottom-side placement, file separation, and components assembled by hand.

Compare the supplier’s placement preview with the assembly drawing, especially around connectors, polarized parts, and pin-one indicators. A column headed “Rotation” does not establish how a particular footprint’s zero orientation maps to the physical component. Route discrepancies to the designer and assembler for resolution; do not rotate every bottom-side part as a blanket correction.

If R12 exists in the CPL but not in the fitted BOM, stop and identify why. It may be intentionally omitted, assigned to another variant, or missing from the purchasing list. Document the answer instead of leaving the supplier to guess.

5. Add requirements and acceptance notes

Create a short requirements sheet owned by the project team. Record the approved board dimensions, layer count, material requirements, thickness, copper requirements, finish, mask and legend requirements, and any special construction. For controlled impedance, include the agreed targets and supporting design information rather than asking the supplier to infer them.

Separate mandatory requirements from preferences. For example, “preferred delivery date” invites a schedule proposal; “shipment must arrive before the installation window” describes a project constraint. Any unconfirmed technical entry should be labeled as an open question, not silently filled with an assumed standard value.

For assembly, identify requested inspection, programming, and testing, along with what evidence is expected at delivery. “Fully tested” is incomplete without a defined procedure and pass criteria. Ask who provides fixtures, firmware, and reference units. If requirements are still being developed, request separate pricing for the agreed scope and the unresolved options.

State which document controls if two instructions disagree. Ideally, remove the disagreement before requesting a quote. A priority note helps manage documents; it does not make an unresolved technical conflict safe to ignore.

For example, suppose the request form specifies one finish while the fabrication drawing specifies another. Ask the design owner to confirm the intended finish, correct the inconsistent document, and send an updated package. Do not ask purchasing to decide which entry looks more recent. Apply the same process to contradictory quantities, material notes, and fitted-component lists.

6. Package and name the files

Name the quotation archive with a project identifier, board revision, assembly variant, and release date so the supplier can identify the intended build without opening every file. Keep fabrication, assembly, and requirements documents organized consistently. The fictional structure below is a suggested naming pattern; adapt it to the supplier’s upload requirements.

SensorHub_RevC_VariantA_RFQ_2026-10-03.zip
  00_README.txt
  fabrication/
    SensorHub_RevC_Gerbers.zip
    SensorHub_RevC_FabricationDrawing.pdf
  assembly/
    SensorHub_RevC_VariantA_BOM.csv
    SensorHub_RevC_VariantA_CPL.csv
    SensorHub_RevC_VariantA_AssemblyDrawing.pdf
  requirements/
    SensorHub_RevC_VariantA_QuoteRequirements.pdf

The Gerber archive should contain the complete agreed fabrication export, including drilling data. Some portals want a flat archive instead of nested folders; repackage to match their instructions without mixing revisions.

In the README, name the project, revision, variant, requested quantities, design contact, and files included. Add a status line such as “For quotation only; production release requires separate approval.” List open questions and explain whether panelization is already defined or should be proposed by the supplier.

A replacement package should have a new release identifier and a brief change note. Ask the supplier to acknowledge that it supersedes the previous package. Keep the previous release internally for traceability, but exclude obsolete exports from the new archive.

For repeat orders, identify the previous purchase order and approved release, but still verify the files being requested now. A familiar project name is not proof that the board, component selection, or test instructions remain unchanged. If the supplier proposes using stored data, ask it to confirm the specific revision and variant before the order advances.

7. Run the release checklist

Check technical content, file consistency, and commercial scope before sending the RFQ package. Assign design checks to the design owner and purchasing checks to the buyer, then have one person assemble the final archive. Reopen that archive after both checks so late edits cannot silently create a mixed release.

1. Identity: confirm that filenames, drawing title blocks, BOM, and request all identify the same revision and variant.
2. Completeness: compare the archive contents with the README. Open every required file and check for empty or unreadable exports.
3. Geometry: compare the exported board outline, dimensions, and hole information with the approved drawing.
4. Population: reconcile fitted designators across the BOM, placement data, and assembly drawing; explain every exception.
5. Spreadsheet integrity: check that part numbers remain text and have not become dates, rounded numbers, or scientific notation.
6. Scope: confirm board quantity, supplied materials, substitutions, testing, delivery destination, and unresolved questions.
7. Transfer: reopen the final archive and check the supplier’s upload summary or acknowledgment against what was sent.

Save the exact sent archive with the quotation record. When comparing offers, request clarification wherever suppliers priced different materials, component alternatives, testing, or delivery assumptions. Resolve those differences before treating the lowest total as a like-for-like comparison.

Maintain a short question log with an owner and resolution for each open item. Close it against the final quotation package so the next buyer can understand what was agreed without reconstructing the entire conversation.

8. Write the quotation request

Connect the technical package to a clear commercial request by stating the product, revision, variant, quantities, and services to be priced. Ask the supplier to identify assumptions, exclusions, substitutions, and lead time in its offer. The example below also distinguishes a quotation request from production authorization.

Please quote 50 and 200 assembled SensorHub boards, revision C, variant A, using the attached RFQ package dated 2026-10-03. Include board fabrication, component sourcing, and assembly. Please list exclusions, proposed substitutions, open technical questions, lead time, and quotation validity. Identify the attached package in your offer. This request is for quotation only.

Add the actual delivery destination and requested testing scope. Replace every example detail before sending. If anything changes during discussion, update the controlled requirements rather than relying on scattered email corrections.

Frequently asked questions

Can I request a quote before all the files are ready?

Yes, you can ask whether a supplier will provide a preliminary estimate. Clearly identify missing information and ask which assumptions underpin the price. A planning estimate should not be treated as confirmation of the final build cost. Send the completed package for a revised offer before making a production commitment.

Do I need a BOM and CPL for bare PCBs?

They are generally associated with assembly, so they may not be needed for a bare-board quotation. Ask the fabricator what its quoting process requires. If you also want component sourcing or assembly priced, state that scope explicitly and provide the corresponding information rather than assuming it is included.

Can screenshots or a schematic replace manufacturing files?

Use them as supporting context unless the supplier specifically agrees to a different engineering service. A screenshot is useful for explaining a question but does not establish a complete, controlled manufacturing dataset. If only an early schematic exists, describe the project as needing design or production-data preparation before fabrication.

What should I do when the supplier changes the files?

Request a description of the changes and the files or drawings affected. Have the appropriate design owner review the proposal, including any changes to panelization or assembly interpretation. Record the approved version and confirm which package will be used for production. Do not assume that approving a price also approves every technical change.