How to Vet a PCB Manufacturer Without Slowing Your Build Schedule

When you need to produce prototypes, a short run of boards, or scale into sustained manufacturing, how do you qualify the PCB and PCBA vendors you will use? There are multiple questions to answer when vetting a candidate PCB manufacturer. This article offers a practical guide on how to evaluate a PCB manufacturer's capabilities and quality standards without causing unnecessary delays to your production timeline.

Key Takeaways

• Confirm manufacturing fit early. Qualify PCB/PCBA vendors by verifying stackup support, material availability, impedance tolerances, and lead-time options to avoid delays caused by non-standard requirements or long material procurement.
• Use responsiveness as a signal. Quote turnaround time (ideally 3–4 business days) is a strong indicator of a manufacturer’s capability, organization, and willingness to support you during production issues.
• Check certifications and compliance. Ensure vendors hold the right certifications (e.g., ISO 9001, ISO 13485, UL, ITAR, NADCAP, IPC Class 3) for your product’s industry to prevent legal, quality, and program risks.
• Validate claims with process insight. Go beyond capability statements by using audits, site visits, test data, or test boards to confirm a manufacturer can consistently meet your quality and reliability requirements.

Can They Support Your Stackup?

Some builds have very specific requirements on materials, which may be defined by the designer for multiple reasons. In other cases, any PCB stackup will work as long as the copper weights, material thicknesses, tolerances, etc. are within spec. Here are some points to check:

• Available standard stackups: Most PCB manufacturers have a set of standard stackups; these constructions consist of materials (types and thicknesses) they always keep in-stock. If their standard stackup does not conform to your specifications, then you will need to look at their materials options.
• Materials list: If a non-standard stackup is needed, verify the manufacturer can procure your desired material or an equivalent with reasonable lead time. While this may not be specified on the company’s website, a manufacturer can provide confirmation (by phone or email) they can procure a specific material.
• Impedance tolerances: Some manufacturers will list the width (or impedance) tolerances they can guarantee for their standard and/or custom stackups.

If a standard stackup will not meet your requirements, which is typical for high-voltage power electronics or high-speed PCBs, then inquire as to the materials they can quickly procure. If a manufacturer can’t procure a specialty material in a few weeks maximum, then consider looking elsewhere rather than sending your files for quote.

Lead Time Options

The “typical” lead times for PCBs and PCBAs depend on the production volume and service level being requested. At volume, manufacturers should be able to guarantee a certain volume per month with a fixed lead time to the ship date for the first batch of PCBs. This number varies based on the specific design, the state of the supply chain, and a manufacturer’s available capacity.

For prototyping, lead times are much more standardized and a manufacturer is better able to guarantee specific timeframes. Standard lead time for rigid PCBs is typically 20 business days, with quick-turn options at 1, 2, 3, 5, 7, 10, or 15 days. A 4-layer board with in-stock FR4 might ship in 10 days, but that same design with Rogers 4350B could take 20+ days if they need to order material. Similar lead times apply for PCBAs, but some service levels (on-the-line flashing, box builds, etc.) require a custom quote.

Can the PCB fab build your boards fast enough? Can the assembler build the PCBAs fast enough? If not, consider looking elsewhere.

Quote Turnaround Time as a Responsiveness Indicator

Quote turnaround time is a good indicator of how a manufacturer values your business relationship and how quickly they can handle production issues. If a manufacturer can't deliver a quote in 3-4 business days, one of following things is occurring:

1. Your order is too small for the manufacturer to care about and is not worth their attention.
2. They're trying to figure out if they can actually build your board.
3. Something is broken in their systems.

All three of these outcomes are clear indicators that you should work with a different company.

Manufacturers optimize for customer acquisition because once you order from a fabricator, you typically stick with them. The first order might be five boards, but if your product succeeds, you'll be ordering 100 boards, then 500. Capturing that initial customer means securing potentially 5-10 years of repeat business. If the manufacturer doesn’t view your design as worth their time, and they don’t want to win your business, then they should be courteous and tell you this is the case.

In the case where they are taking a long time to figure out whether they can build your board, chances are they cannot build the PCBs in-house. In this case, if they do get to you with a quote, they will likely outsource the design and charge a mark-up.

When a fabrication issue surfaces mid-production and you need a response in hours, not days, that same disorganization will surface again. The quote turnaround time is your early warning signal.

Certifications and PCB/PCBA Qualification

There are multiple certifications that PCB manufacturers, CMs, value-added resellers (VARs), and ODMs might carry:

• ISO-9001 Quality Management System standard: ISO 9001 is a basic quality certification that requires documented procedures for every step of fabrication. The goal is to implement procedures to trace any quality issue back to its source.
• ISO-13485 for medical devices: ISO 13485 is the QMS standard for medical device manufacturing. It provides a framework for design, manufacture, and distribution of safe medical devices that comply with regulatory requirements while focusing on risk management and high-quality production.
• UL for consumer products: Underwriters Laboratories (UL) certification is a consumer and commercial appliances product marking that confirms the product meets safety standards for electrical and fire hazards. Manufacturers that produce these products may also be certified to perform UL testing.
• ITAR for aerospace and defense: Manufacturers of items on the USML or dual-use products require an ITAR manufacturer’s certification issued by the DDTC. Otherwise, they can't legally handle controlled technical data for these products. I've seen projects where engineers sent designs with export-controlled technology to an overseas fab that wasn't ITAR compliant. The company got flagged during an audit, had to pull the product, faced potential fines, and lost the contract. The board itself might have been perfect and there was no actual theft of IP, but the legal exposure killed the entire program.
• NADCAP for aerospace and defense: The National Aerospace and Defense Contractors Accreditation Program (NADCAP) is an industry-managed accreditation program for aerospace and defense products. It is a product-level quality certification that verifies a supplier can meet quality standards for "special processes" like heat treating, welding, or non-destructive testing.
• IPC Class 3 for high-reliability products: While this is not a certification, some manufacturers offer this level of qualification as part of their service offerings. Class 3 places tighter acceptance criteria for annular ring, via quality, solder mask registration, and other aspects of the PCBA, which ultimately flow back to the PCB design constraints.

Process Auditing

Capability statements only tell you what a manufacturer claims they can do and what they are willing to guarantee. Typically, for short runs of boards or for prototyping, process auditing is not performed due to the time and effort involved.

• Site visits: A site visit is one way to inspect whether a manufacturer has quality operations in place. During a site visit, you’ll have a chance to see production activities in action, the cleanliness and quality of facilities, and the state of the manufacturer’s production equipment.
• Test or SPC data: As part of process control, manufacturers regularly capture data from their production equipment. If certain aspects of the board are critical in a particular design, it’s appropriate to request test data focusing on multiple aspects of a fabricated PCB or PCBA:
  • Surface finish quality
  • Warp/bend/bow/twist measurements
  • Prevalence of BGA/no-lead part defects
  • Etch factor variation
  • Trace width tolerances
  • Board dimension tolerances
  • Solder mask registration tolerances
  • Drill position (annular ring) tolerances
• Test boards: OEMs producing at volume may develop their own test vehicles and place these into production with a candidate manufacturer. These test vehicles can then be inspected for defects. Test vehicles should include all the features that are expected to be implemented in any builds that will be placed in production with a candidate manufacturer.
• 3rd-party auditing: If test boards are procured, these can be sent to an external testing lab for validation.

Large companies that have strict requirements on build quality might qualify certain fabricators and assemblers for specific design categories they produce. This is assessed with a combination of the above auditing steps, and audits are performed periodically to ensure a fabricator/assembler is maintaining the expected quality standards.

Vetting Builds Trust

Vetting a manufacturer is about building a business relationship. If a candidate manufacturer values your business and wants to take on future work from your company, they should be willing to help you fully understand and verify their capabilities. Once you fully gather the capabilities required for your design, set these constraints as design rules in your PCB design software to ensure your design will pass a manufacturer’s DFM review.

Whether you need to build reliable power electronics or advanced digital systems, use Altium’s complete set of PCB design features and world-class CAD tools. Altium provides the world’s premier electronic product development platform, complete with the industry’s best PCB design tools and cross-disciplinary collaboration features for advanced design teams. Learn more today.

Frequently Asked Questions

How do I know if a PCB manufacturer can support my specific stackup and materials?

Ask whether the manufacturer has standard stackups that meet your requirements and, if not, whether they can reliably source your specified materials (or approved equivalents) within an acceptable lead time. Also confirm the impedance and tolerance guarantees they can hold for both standard and custom stackups.

What is a reasonable lead time for PCB and PCBA manufacturing?

For prototypes, rigid PCBs typically ship in ~20 business days, with quick-turn options ranging from 1 to 15 days depending on complexity and material availability. PCBAs follow similar timelines, but added services (programming, box build, testing) may require custom quotes. If a vendor cannot meet your schedule, they may not be a good fit.

Why is quote turnaround time so important when vetting a manufacturer?

Quote turnaround time is an early indicator of responsiveness and operational health. If a vendor cannot deliver a quote within 3–4 business days, it may signal capacity issues, disorganization, or lack of interest in your business—problems that often resurface during production.

Which certifications should I look for in a PCB or PCBA vendor?

The required certifications depend on your industry. Common examples include ISO 9001 for general quality management, ISO 13485 for medical devices, UL for consumer products, ITAR and NADCAP for aerospace and defense, and IPC Class 3 for high-reliability designs. Choosing a properly certified vendor reduces legal, quality, and program risk.