Compare HDI PCB quotations only after each supplier has priced the same interconnect drawing and acceptance scope. A lower unit price can reflect a different via construction, an omitted test or a different delivery quantity. Resolve those differences before ranking the totals.
The HDI cost guide explains the main drivers. This worksheet addresses the next step: reconciling actual offers against one controlled technical baseline. The monetary example below is invented arithmetic, not market pricing or a supplier quotation.
Give the comparison a fixed baseline
Create a short baseline sheet with a revision identifier. Attach the fabrication drawing, copper files, drill definitions and approved stack proposal associated with that revision. Record the number of finished boards required, the delivery format, material construction, finish, copper requirements and electrical test scope. Link every offer to this same release package.
A supplier response may be useful without being fully compliant. Label it as an alternative rather than silently treating it as the baseline offer. If one factory proposes a different material or transition style, keep the proposed change visible until engineering has accepted it. Price is only comparable after you know what the price buys.
Replace “HDI vias” with a span-by-span table
For each interconnect type, identify the start and stop layers, finished feature requirements and any filling or planarization requirement. Distinguish laser-drilled microvias from mechanically drilled blind, buried or through holes. Where successive transitions exist, specify their arrangement and the relevant landing geometry. A general via-in-pad note does not fully describe all these operations.
| Baseline item | Supplier response to request | Comparison status |
|---|---|---|
| Each via span and transition arrangement | Confirmed drawing revision, or marked alternative | Unresolved if only “HDI supported” is stated |
| Fill and surface requirements | Process and acceptance interpretation | Different processing must remain a technical exception |
| Stack construction and material | Specific proposed construction, with substitutions listed | A family name alone is incomplete |
| Test and documentation | Included tests, reports and exclusions | Missing scope cannot be treated as a saving |
Ask the supplier to explain the manufacturing sequence for the proposed structure. Do not derive the total number of press operations from the copper-layer count alone. The sequential-lamination discussion provides context for that question. This review is about confirming what each offer includes; it does not require suppliers to disclose proprietary process recipes.
Separate an alternative process from a discount
Eurocircuits describes panel sharing and predefined constructions in its HDI service. That illustrates why an offer based on a standard pooled construction and one based on a dedicated production panel can have different commercial assumptions. It does not establish that either approach is appropriate for your design.
Suppose supplier A confirms the released via drawing, while supplier B changes a transition to fit its standard process. B may have a valuable proposal, but the two offers are not yet prices for the same board. Ask the designer to evaluate the changed escape, clearances, reference continuity and fabrication evidence. Record the validation work separately from the quoted board cost.
Keep a response column for “confirmed,” “exception” and “not stated.” A blank cell should not default to confirmed. Close technical exceptions in writing against a revised drawing before converting the comparison into a purchase decision. If the design changes, invite all shortlisted suppliers to quote that revised baseline so the comparison remains fair.
Use total lot cost without hiding exclusions
Separate recurring board charges from one-time setup, agreed reports, shipping and other applicable charges. Also record whether the quote is per individual board, per array or per fabrication panel. A denominator error can overwhelm a genuine process saving.
Consider an illustrative requirement for 100 accepted individual boards. Offer A lists a $250 setup charge and $18 per board. Offer B lists $100 setup and $19 per board, with an additional $120 charge for a required report. Excluding shipping and taxes equally, the scoped totals are:
- A: $250 + 100 × $18 = $2,050.
- B: $100 + 100 × $19 + $120 = $2,120.
B’s smaller setup charge does not make its total lower in this example. If the report is not actually required, that is a scope decision to resolve consistently for both offers, not a reason to add or remove charges selectively. Do not invent missing supplier charges to complete a spreadsheet; request clarification and retain an unresolved total until it arrives.
For repeat orders, ask which setup charges recur and which do not. Do not assume ownership or reuse of tooling from a line labeled “NRE.” Compare prototype and production quantities separately, using confirmed terms for each. A useful cost model preserves both the first-lot total and the repeat-lot assumptions.
Define delivery and acceptance in the same units
Record the point at which lead time starts: order acceptance, payment, engineering approval or another stated milestone. Distinguish fabrication completion from receipt at the assembly site. If an expedited offer excludes normal technical review time, flag that dependency rather than treating its headline lead time as a guaranteed arrival date.
Likewise, confirm what quantity is promised and what happens when boards fail the agreed acceptance criteria. Keep permissible quantity variation, lot traceability and report delivery visible. A price per manufactured board and a price for an accepted delivered quantity answer different commercial questions. These details should be taken from the supplier’s actual offer, not inferred from a previous order.
Close the comparison with an exception register
- Identify the exact release revision priced by each supplier.
- Confirm all via spans and required processing.
- List substitutions and unresolved technical deviations.
- Normalize quantity units, one-time charges and required reports.
- Record delivery milestones and acceptance responsibilities.
- Retain the approved exception register with the order package.
The cost estimator can organize an early budget, but a planning estimate does not replace this reconciliation. Use the manufacturing library to resolve construction questions, or request a quote review with the baseline sheet and marked exceptions. The desired outcome is a comparison that another engineer can reproduce from the same documents.
Source reviewed 9 October 2026. Prices and offers in the example are hypothetical; the worksheet is an original comparison method, not a statement of supplier pricing or capability.