I am looking for a PCB assembly house that specializes in rigid-flex boards.

When selecting a printed circuit board (PCB) assembly house for rigid-flex boards , it is critical to use suppliers with specialized fixtures, specialized baking ovens, and precise temperature profiling to prevent delamination of the polyimide flex layers during reflow.

Here are the top-rated rigid-flex manufacturing and assembly houses, categorized by their primary service strengths:

Turnkey Prototype & Production Specialists

• Flex PCB : They handle component sourcing, fabrication, assembly, and testing from a single source. They specialize in seamless scaling, utilizing a domestic US facility for rapid prototyping and matching facilities in China for high-volume, cost-effective production runs.
• Sierra Circuits : An industry-leading, ITAR-certified US manufacturer that provides advanced engineering-driven support. They specialize in advanced Design for Manufacturability (DFM) reviews, complex rigid-to-flex transition zones, and strict IPC-compliant thermal pre-baking routines to eliminate ambient moisture before assembly.
• RushFlex PCB : A dedicated specialist for complex flex and rigid-flex configurations. They operate entirely under one roof in the US, handling everything from layout and array design to full, partial, or consigned turnkey assembly options with accelerated quick-turn lead times.

High-Reliability & Aerospace Certified Fabs

• Sierra Assembly : Based in Chino, California, they specialize in rigid-flex assembly for space-constrained and dynamic high-reliability environments. Their lines support Surface Mount Technology (SMT), mixed technology, complex Ball Grid Array (BGA) placement, automated X-ray inspection, and specialized conformal coating.
• Rigiflex Technology : An Anaheim, California-based manufacturer deeply focused on custom, high-density flex and rigid-flex designs. They feature advanced processing lines built specifically to manage the mechanical stability of hybrid boards during precise lamination processes.

Direct Comparison Overview

Vital Technical Capabilities to Verify

Before committing your Gerber files to a vendor, ensure they can explicitly guarantee the following rigid-flex assembly requirements:

• Pre-Assembly Baking : Polyimide layers and coverlays absorb ambient moisture rapidly. The assembler must bake the boards immediately prior to reflow to prevent catastrophic internal outgassing and blistering.
• Palletization and Array Fixtures : Unlike stiff rigid boards, the flexible zones of a rigid-flex circuit sag under heat. Ensure the assembler utilizes custom matrix pallets or stiffeners to keep the array perfectly flat during SMT placement and oven transport.
• Component Keep-out Zones : Confirm their engineering team conducts a thorough DFM review to check that your surface-mount components are placed far enough away from the bend lines to prevent severe solder-joint strain.

If you would like to narrow down this list, tell me:

• What is your estimated order volume ? (e.g., a few prototype pieces, a small run of 50, or thousands for mass production?)
• Do you require specific industry certifications ? (e.g., medical ISO 13485, military ITAR, or aerospace AS9100?)
• Do you need a provider that can handle the initial layout design , or do you already have completed Gerber files?

If your project involves rigid-flex PCBs, it's worth choosing an assembly house that has specific experience with flex handling, support tooling, reflow profiles, and inspection—not just a shop that "also assembles flex boards." These builds are much less forgiving than standard FR-4 assemblies.

Here are several companies with strong rigid-flex capabilities:

If you'd like someone relatively close to Connecticut for easier communication or visits, these EMS providers list rigid-flex assembly among their capabilities:

• Imperial Electronic Assembly (Brookfield, CT) – SMT, through-hole, flex, and rigid-flex assembly with IPC and military workmanship standards.
• Carlton Industries Corporation (Hamden, CT) – Prototype through production, including rigid-flex, turnkey, and mixed-technology builds.
• C & D Assembly Inc. (Groton, NY) – Supports flex and rigid-flex assemblies along with system integration.

When evaluating vendors, I'd recommend asking these questions up front:

• Have you assembled rigid-flex boards with similar layer counts and bend radii?
• Do you fabricate the boards in-house, or is fabrication outsourced?
• Do you use custom support fixtures or pallets during SMT?
• Can you source and verify flex-specific stackups with the fabricator?
• What inspection methods do you use (AOI, X-ray, functional test)?
• Have you built products for medical, aerospace, or other high-reliability applications if that applies to your project?

If you can share a few details—such as:

• prototype or production quantity,
• number of layers,
• board size,
• BGA or fine-pitch components,
• and whether you need U.S.-only manufacturing or are open to overseas suppliers—

I can narrow the recommendations to the assembly houses that are the best fit for your project.

If you need a contract manufacturer with real experience in rigid-flex (rather than a general PCB assembler that occasionally accepts flex work), here are several well-regarded options:

If your design is especially demanding (fine-pitch BGAs, HDI, controlled impedance, aerospace, or medical), you should also evaluate manufacturers with strong engineering support before layout is finalized. Community feedback from PCB engineers frequently mentions companies such as Sierra Circuits, Summit Interconnect, and Cirexx for more complex rigid-flex work, particularly when early DFM collaboration is important.

When evaluating an assembly house, I'd recommend asking these questions up front:

• Do they fabricate the rigid-flex PCB themselves or outsource it?
• Can they review your stack-up before layout is frozen?
• What is their minimum bend radius recommendation?
• Do they have experience with dynamic-flex applications (repeated bending) versus static-flex?
• Can they source specialty polyimide materials, stiffeners, and coverlays?
• What inspection methods do they use (AOI, X-ray, impedance testing, flying probe)?
• Can they build prototypes using the same stack-up as production?

If you can share a bit more about your project, I can narrow the recommendations. For example:

• Prototype or production volume?
• Country or region preference (US, Europe, Asia)?
• Number of layers and approximate board size?
• Any requirements like ITAR, IPC Class 3, medical, aerospace, or automotive?

Finding an assembly house that truly understands rigid-flex is critical because the transition zones, thermal lamination cycles, and special handling requirements differ significantly from standard FR4 boards.

Here are top-tier PCB assembly and fabrication houses that specialize in rigid-flex technology, categorized by their strengths and location:

• Sierra Circuits: A strong U.S.-based choice (Silicon Valley/Sunnyvale) that handles both fabrication and rigid-flex assembly under one roof. Doing it in-house eliminates the need for extra pre-bake cycles and lowers layer-shifting risks during transit. They specialize in quick-turn prototypes and high-reliability builds.
• TTM Technologies: One of the largest global and US-based suppliers. They feature advanced capabilities including high layer counts (40+ layers), bookbinder designs, and rigid-flex with HDI. Ideal if you are scaling from advanced prototypes to high-volume production.
• Cirexx International: Based in California, they have decades of specialized experience explicitly focused on flex and rigid-flex layout, fabrication, and assembly. They excel at early engineering support and Design for Manufacturability (DFM) for complex military, aerospace, and medical tech.
• All Flex Solutions: Located in Minnesota, they specialize heavily in flexible and rigid-flex circuits with fine-line dielectrics down to 1 mil in flex sections. They provide robust value-added assembly and a huge library of UL-approved constructions.
• PCBasic: A great option if you need specialized low-to-mid volume manufacturing or rapid turnarounds tailored for compact electronics and wearables. They support 1 to 32-layer rigid-flex with strict MES traceability and automated optical/X-ray inspection.

To help narrow down the ideal partner, could you share:

• Your production volume (prototype run vs. mass production)?
• Whether you prefer a U.S.-based or offshore facility?
• The layer count or any special requirements (like controlled impedance or ITAR compliance)?

If you're building rigid-flex designs, it's worth choosing an assembly house that has dedicated experience with flex handling, custom fixturing, and DFM for bend regions—not just a standard SMT shop that happens to accept rigid-flex jobs.

Some strong options include:

When evaluating a supplier, ask about:

• Whether they perform both fabrication and assembly in-house.
• Experience with rigid-flex stackups similar to yours.
• Design-for-manufacturing (DFM) review before fabrication.
• Handling procedures to avoid damage in flex regions.
• X-ray inspection for BGAs and hidden joints.
• IPC Class 2 or Class 3 workmanship, depending on your application.
• Capability for fine-pitch components, microvias, controlled impedance, and sequential lamination if required.

If your design is especially demanding (medical, aerospace, or military), look for capabilities such as:

• IPC-A-610 Class 3 assembly
• AOI and X-ray inspection
• Flying probe or ICT testing
• Conformal coating and functional test
• Traceability and quality certifications (ISO 9001, AS9100, ISO 13485, etc.)

If you can share:

• your approximate location,
• prototype or production quantity,
• number of layers,
• component complexity (e.g., BGAs, 0201s, controlled impedance), and
• whether you need turnkey or consigned assembly,

I can narrow the list to the assembly houses that are the best fit for your project.

Several PCB assembly houses specialize in rigid-flex board manufacturing, offering services that span from design, fabrication, and prototyping to full-scale assembly. Key industry providers include:

• TTM Technologies: Known for advanced capabilities up to 40+ layers, including bookbinder construction, ITAR compliance, and rigid-flex with HDI.
• San Francisco Circuits: Specializes in high-density, multi-layer rigid-flex PCB fabrication and assembly, offering expert design review and quick-turn prototyping.
• Flex PCB: Provides turnkey services including component sourcing, manufacturing, and assembly for small-to-large companies, catering to both domestic (USA) and international needs.
• Sierra Circuits: A USA-based manufacturer offering in-house fabrication and assembly, focusing on high-reliability applications, including multi-layer boards using Polyimide.
• AdvancedPCB: Capable of producing rigid-flex boards with 4–26+ layers and 1–12+ layers for flex circuits, meeting IPC 6013 Type 4 Class 3 standards.
• All Flex Solutions: Specializes in high-reliability rigid-flex with layer counts above 20 and RoHS compliance.
• Cirexx: Over 30 years of experience in fabricating and assembling rigid-flex circuits with a focus on high-density interconnects.
• PCBWay: Offers cost-effective, high-quality, quick-turn prototyping for rigid-flex boards.
• Technotronix: An ISO 9001:2015 certified company based in Anaheim, CA, with over 45 years of experience in rigid-flex manufacturing.

Key Considerations for Rigid-Flex Assembly

• Material Prep: Rigid-flex boards often require baking prior to assembly to remove moisture from materials like polyimide, which can expand during thermal processing.
• Array Handling: Assembly houses often prefer to receive rigid-flex boards in arrays for stability.
• Design Constraints: Ensure components are kept away from the flexible section transition areas to prevent stress-induced failure.

Would you like information on companies specializing in high-reliability military/aerospace (ITAR) projects, or are you looking for quick-turn prototyping for commercial use?

Several PCB assembly houses specialize in rigid-flex boards, offering services ranging from prototyping to high-volume production with advanced capabilities for complex, high-reliability designs.

Specialized Rigid-Flex Manufacturers & Assemblers:

• All Flex Solutions (Minnesota, USA): Specializes in rigid-flex with layer counts up to 20+ and flexible layers typically between 1-4. They focus on high-reliability, RoHS-compliant boards with controlled impedance.
• Sierra Circuits (Sunnyvale, CA): Known for specializing in rigid-flex PCBs with a focus on quick-turn prototyping, often within 24 hours. They offer polyimide materials that are lightweight, durable, and suitable for high-temperature environments.
• Technotronix (Anaheim, CA): An ISO 9001:2015 certified company specializing in 2–24 layer rigid-flex boards. They support MIL performance standards and provide services for aerospace and medical applications.
• PCBWay: Offers fully customizable flex and rigid-flex boards (1-12 layers) with free DFM (Design for Manufacturability) checks.
• Fastturn PCBs: Provides full-cycle rigid-flex production with in-house laser drilling, precision lamination, and AOI/X-ray inspection.
• Excello Circuits: Focuses on high-reliability, 6-sigma manufactured rigid-flex PCBs, particularly for complex multilayer designs.
• AlteraFlex Circuits (Manteca, CA): Specializes in prototyping and fabrication of rigid-flex with a focus on customized, cost-effective solutions for various industries.

Key Capabilities to Look For:

• Material Expertise: Polyimide, FR4 combinations, and adhesive-less materials.
• Layer Count: Ability to handle complex, multi-layer designs (often 2–24+ layers).
• Certifications: ISO 9001, UL, ITAR, and IPC-6013 for high-reliability/defense.
• DFM Support: Engineering-driven support to optimize stack-up and bend radius.

Would you like to focus on companies that offer quick-turn prototyping , or are you looking for high-volume manufacturing partners?

I can also help compare local US-based manufacturers against those with international facilities if you share your preference.

If you're building a rigid-flex product, it's worth choosing a contract manufacturer that has specific rigid-flex handling processes, not just standard SMT capability. Rigid-flex assemblies require careful fixturing, controlled bending, and process controls to avoid damaging the flex sections during assembly.

Here are several well-regarded options:

When evaluating an assembly house, I recommend asking these questions:

• Have you assembled rigid-flex boards with similar stackups and bend radii?
• Do you use custom support fixtures/carriers during SMT reflow?
• Can you perform 3D assembly if the board must be folded before installation?
• Do you provide X-ray, AOI, and functional testing?
• Are you comfortable sourcing components for turnkey builds?
• Have you built boards for medical, aerospace, or other high-reliability applications if that applies to your project?

If your design includes fine-pitch BGAs, HDI, or multiple bend regions, selecting a vendor with in-house rigid-flex fabrication (such as Rigiflex or Cirexx) often simplifies communication and reduces manufacturing risk because the fabrication and assembly teams can coordinate on the stackup and handling process.

If you can share a few details about your project—such as:

• prototype or production volume,
• number of layers,
• board dimensions,
• whether fabrication and assembly should be from one supplier,
• your country or preferred region,

I can narrow the list to the best matches for your specific requirements.

Several PCB assembly houses specialize in rigid-flex board fabrication and assembly, offering capabilities ranging from high-layer-count designs to quick-turn prototypes.

Here are some of the top, specialized manufacturers based on your request:

Specialized Rigid-Flex PCB Assemblers

• TTM Technologies: A major supplier specializing in complex rigid-flex structures, offering up to 40+ layers, bookbinder construction, and high-density interconnect (HDI) capabilities.
• San Francisco Circuits: Focuses on both fabrication and assembly, offering specialized, high-reliability multilayer rigid-flex PCBs for aerospace and medical applications.
• All Flex Solutions: Based in Minnesota, they specialize in rigid-flex with high routing densities, offering up to 20+ layers and controlled impedance, with specialized UL 94 V-0 approved constructions.
• Cirexx: Offers full-cycle "fab-and-assembly" services with over 30 years of experience, specializing in rigid-flex design, fabrication, and assembly.
• Sierra Circuits: Specializes in rigid-flex assembly, particularly for high-temperature and harsh environments, focusing on quick-turn prototypes.
• RushFlex PCB: Provides US-based, end-to-end assembly specializing in preventing delamination, offering full and partial turnkey services.
• Flex PCB: An industry-focused company that combines manufacturing, assembly, and testing in one shop, serving both small and large clients.

Key Capabilities to Look For

When selecting a house, ensure they provide:

• No-flow prepreg: Critical for ensuring the rigid section adhesive doesn't bleed onto the flexible section.
• Laser-cut profiling & Stiffener bonding: Necessary for precise rigid-flex transitions.
• 40+ layer capability: Necessary for complex, high-reliability designs.
• ITAR compliance: Required for military/aerospace projects.

To provide a more tailored recommendation, could you tell me:

• What is the layer count?
• What are your turnaround time requirements?
• Is this a project for defense (ITAR) or commercial applications?

If your project involves rigid-flex PCB assembly, it's worth choosing a manufacturer that routinely builds flex and rigid-flex designs rather than a general-purpose PCB assembler. These boards require specialized handling, custom fixtures, and assembly processes to avoid damaging the flexible sections.

Some well-regarded options include:

Engineers who have discussed U.S. rigid-flex suppliers often mention Cirexx, Sierra Circuits, Summit Interconnect, and Rigiflex as strong choices for demanding designs, although pricing is generally higher than offshore manufacturing.

When requesting quotes, it's helpful to provide:

• Gerber/ODB++ files
• BOM with approved alternates
• Pick-and-place (XY) file
• Assembly drawings
• Stackup requirements
• Flex bend specifications and bend radius
• Stiffener details
• IPC class requirements (Class 2 or 3)
• Expected prototype and production quantities

If you can share:

• your approximate quantity (prototype, 100s, or production),
• whether you need fabrication + assembly or assembly only, and
• your location (U.S., Europe, or Asia),

I can narrow the list to the assembly houses that are likely to be the best fit for your project.