BOM, DNP and Revision Checklist for PCBA

Release one BOM for one assembly variant

For a useful PCBA quotation, identify the board revision, assembly variant and BOM revision together. List what should be fitted, what should remain unpopulated and who can approve a change. Send the matching placement data and assembly drawing with the same release identifier.

This checklist is for engineers and buyers preparing prototype, small-batch or repeat production data. It is a suggested handover method, not a claim that a particular CAD export is ready for production. Confirm the file format and review requirements with your assembly partner.

What does DNP mean in a PCBA BOM?

DNP means do not populate: the component is not to be fitted for the specified assembly variant. A footprint can still be present on the board. A blank manufacturer part number does not reliably communicate that instruction. State the fit status explicitly and identify the affected reference designators.

CAD export settings matter. KiCad distinguishes DNP, exclusion from a BOM and exclusion from the board; its export options can also omit DNP rows. Check the actual exported file rather than assuming every assembly option remains visible. See the KiCad Schematic Editor documentation for that tool's attribute definitions.

A practical BOM handover table

A DNP example that avoids an ambiguous blank row

Suppose an illustrative controller board has two commercial variants. For variant A, R15 and R16 are fitted and R17 is DNP. For variant B, R15 is fitted while R16 and R17 are DNP. Keep those decisions in a variant table or release separate, clearly named BOMs. Do not send two unlabeled spreadsheets and expect the assembler to choose.

This is an invented configuration example, not a customer project or an electrical design recommendation. Your design owner must confirm the actual circuit behavior, firmware and test requirements for each variant.

Check the exported files before requesting a quote

1. Freeze the release name. Put the same board revision and assembly variant in the BOM, placement export and assembly drawing. Include a short file manifest.
2. Reconcile reference designators. Resolve duplicate locations, missing fitted parts and differences between the BOM and placement data. Record intentional exclusions instead of deleting unexplained rows.
3. Separate quantity units. State quantities per board and the number of boards requested. Agree whether sourcing allowances, minimum purchase quantities and excess materials are included in the quote.
4. Review fit options. Confirm that DNP settings survived export. Mark the matching drawing and explain any variant-specific test or firmware requirement.
5. Define change authority. Name the role responsible for approving part changes. Refer to the component substitution approval guide when an exact part cannot be sourced.
6. Close open questions. Keep unresolved lines in an issue list. Identify whether each quote assumes an answer or excludes the affected work.

Keep quotation review separate from production release

A quote can be prepared with clearly stated assumptions; a production order needs an approved configuration. If the BOM changes after quotation, identify the changed lines and ask whether sourcing, setup, testing or scheduling must be reviewed again. Reusing an old filename without a revision note makes that review harder.

For repeat orders, include the previously approved release and the proposed changes. For a transfer to a different manufacturing site, confirm the executing site and responsibility for inherited tooling, programs and test documents. An earlier successful build does not establish that a different release or site has already been approved.

Prepare the next project review

Use the PCBA RFQ checklist for the rest of the quotation package. Compare turnkey, consigned and hybrid material responsibilities, then review the component purchasing service scope.

Request a PCBA project review with your board revision, variant, build quantities and delivery country. Describe your project first; agree confidentiality and file-transfer arrangements with sales before sending design files. The enquiry form does not provide a BOM upload field.

Prepared by KeepBestPCBA editorial team. The release tables are suggested project worksheets. Tool-specific DNP terminology is referenced to the KiCad documentation; project acceptance remains subject to your approved design and agreed manufacturing review.