A Guide to PCB Assembly Cost

Are you new to the electronic industry or a veteran of many years experience? It doesn’t matter. What matters is that you understand the accurate estimation of PCB assembly. This will help you set a budget. Understanding it in advance can help you cut costs.

Come along and let’s peel back the layers on PCB assembly costs. Let’s get started.

1.PCB Complexity & Specifications

1.1 PCB Layers

Single-layer or double-layer PCBs are the cheapest. If you choose multilayer PCBs, it costs more due to complex routing and material costs. The more layers the board has, the higher the price.

1.2 PCB Dimension

The size of a PCB is one of the key factors that affect cost. The size of the final project is usually determined by the number of circuits you use. The larger the electronic product you need, the larger the corresponding PCB size will be. Therefore, the assembly price of the factory will also be higher.

1.3 PCB Material

The substrate material of the PCB can have a significant impact. Standard FR-4 is the most common and cost-effective. Specialized substrates such as ceramic materials or flexible PCBs are significantly more expensive.

1.4 PCB Solder Mask Color

Typically speaking, the standard color (green) is the most affordable. If you need custom colors, you will cost more.

1.5 PCB Min Hole Diameter

Drilling requires a drill bit. Small-diameter drill bits are more expensive than standard drill bits. Drilling takes longer when the hole diameter is small, which increases costs.

1.6 PCB Trace Width

Narrower traces and gaps require advanced laser drilling or specialized etching processes. This also increases tooling and production costs.

1.7 PCB Thickness

PCB thickness directly impacts cost through material usage, manufacturing complexity, and assembly requirements, with non-standard or extreme thicknesses (either too thick or too thin) carrying the highest premiums.

1.8 PCB Surface Finishes

Different surface finishes determine different prices.

• HASL is low-cost with less precise.
• Immersion Silver/Tin is moderate cost. However, their boards are prone to shelf-life limitations, impacting inventory and assembly timing.
• ENIG is the highest due to gold plating. But it is ideal for high-reliability or wire-bonding applications. The thicker the immersion gold, the more expensive it is.

2.Bill of Materials (BOM) & Components

The Bill of Materials (BOM) and component selection are central to determining PCB assembly (PCBA) costs.

2.1 Components Procurement Cost

During shortages, you may require much more money to purchase allocated components. And this will drastically inflate BOM costs.

Components from famous brands often cost more than common brands. But their products are more secure and have better performance. The components provided by Orinew are 100% original.

2.2 Component Quantity & Density

Each component adds pick-and-place time. High-component-count boards require longer machine programming and potential nozzle changes. This leads to increased labor and equipment depreciation costs.

Densely packed components have tighter design rules and tighter placement rules. This leads to increased rework costs and reduced yield.

2.3 Component Type & Packaging

(1)Surface-Mount (SMD) vs Through-Hole (THD) Components:

SMD components are generally cheaper to assemble. Since automated pick-and-place machines handle high volumes quickly.

Through-hole components involve manual soldering or wave soldering. They all need additional steps like inserting leads into holes and raising labor and time costs.

(2)Package Complexity & Assembly Difficulty:

BGA/LGA/Flip-Chip: These high-density packages require precise placement and underfill as well as X-ray inspection to verify solder joints. This can increase the inspection and specialized process costs per board.

Odd-form Components: Non-standard shapes may require custom tooling or manual positioning. This leads to higher setup costs and slower assembly speed.

3.Order Volume

The cost per unit is affected by the number of PCBs ordered.

• If you just need a prototype or low-volume quantities, you expect to pay expensive costs. Because you are required to pay additional setup charges. In Orinew, the setup fee standards are as follows: small batch setup fee is RMB 200-300, medium batch setup fee is RMB 300-400, and large batch setup fee is RMB 500.
• But if you purchase bulk orders, you will get a more affordable price. And you don’t have to pay the additional fees mentioned above. The more you purchase, the greater the discount you will enjoy.

4.Assembly Processes

4.1 SMT Processing Cost

(1)Stencil Cost & Model Cost: Before assembly, stencil fabrication is also a hidden fee. When you order bulk orders, you are also required to pay for the model cost.

(2)SMT Placement Cost: The price of the patch is calculated by the number of solder points. The more points, the higher the price. But overall, machine placement is more cost-effective.

4.2 DIP Post Welding Processing Cost

The price of dip post welding also corresponds with the number of holes. The more holes, the higher the price. And there exist two pricing situations.

(1)Wave Soldering: The PCB can stand a high temperature of about 250 degrees. Then you can use machines to solder.

(2)Manual Soldering: The PCB can’t withstand high temperatures. You are required to solder these components by hand. Then you should pay for the labor fees. Compared with wave soldering, it is more expensive.

4.3 Cleaning PCB

(1)No Clean: It can save costs in the short term. But residues from the processing may affect subsequent testing, resulting in increased rework costs.

(2)Clean: Whether it is water-based cleaning or solvent cleaning, it requires operators to operate. And this increases costs.

4.4 Input program testing

You may provide programs for testing. These refer to software program loading, functional verification, and system debugging. This may require additional equipment, fixtures, or labor, increasing labor and equipment costs.

5.Inspection & Testing

PCB assembly can be more expensive if it includes extensive inspection and testing. They can include automated optical inspection (AOI), X-Ray inspection, in-circuit tests (ICT), power-on testing, function testing (FCT), and other necessary testing.

These testing processes can detect defects early on in the production process.

6.Hidden Fees

6.1 PCB Depaneling Cost

It refers to the expenses of separating individual PCBs from a panelized array. The core is affected by factors such as the splitting process, board thickness, size, batch, and material properties.

• Regular-shaped PCBs cost less than special-shaped ones.
• Depaneling of boards thicker than normal is more expensive.
• The unit price of low production is higher than that of high production.
• The depanelingcost of common substrates is lower than that of specializedsubstrates.

6.2 Package Cost

Protective packaging materials like anti-static bags also incur costs. For bulk orders, custom-designed packaging may incur higher costs. Automatic or manual sorting and labeling will also incur costs. Designing your package to meet industry standards (e.g., IPC standards) or customer-specific requirements is also a cost.

6.3 Logistic Costs

They are costs for domestic or international shipping. Prices vary significantly by distance, weight, volume, and delivery speed.

6.4 Lead Time Costs

Orders with standard turnaround times are normal prices. Expedited orders often incur additional charges.

Design for Manufacturability (DFM) Optimization

7.How to Reduce PCB Assembly Costs

Now that we understand the cost structure of PCB assembly. Let’s look at ways to cut costs without sacrificing quality.

7.1 Design for Manufacturability (DFM) Optimization

(1)Minimize Layer Count: You can streamline the number of board layers. Try to use the least number of board layers to achieve the most functions.

(2)Avoid Exotic Features: Restrict blind/buried vias, HDI, or controlled impedance to critical areas. Use standard FR-4 boards instead of specialized substrates whenever possible.

(3)Standardize Component Packaging: Prefer common SMD sizes to reduce stencil change costs.

(4)Ensure Adequate Spacing: Maintain adequate spacing between components. This facilitates soldering and AOI inspection, reducing the risk of rework.

(5)Panel Design: Increase the number of panels and improve material utilization. This can effectively reduce the cost.

7.2 Bill of Materials (BOM) Cost Control

(1)Select Alternative Suppliers: Identify 1-2 alternative suppliers for key components. Avoid cost increases due to price increases or supply delays from the first supplier.

(2)Avoid Over-Engineering: Select passive components with slightly wider tolerances when performance allows. This can save costs.

(3)Standardized Components: Use common components across the BOM to reduce costs.

(4)Consolidated Purchasing: Combine BOMs from multiple projects to reach supplier MOQs. Centralized purchasing to obtain bulk discounts.

Bill of Materials (BOM) Cost Control

7.3 Process Optimization

(1)Reduce Mixed Assembly: Unless necessary, give priority to full SMT design and avoid THT components. Wave soldering or manual soldering installation costs are higher.

(2)No-clean Process: You can choose lead-free no-clean solder paste to save on cleaning step and related costs.

(3)Modular Test: Use universal test fixtures instead of customized ICT. This can reduce test startup costs.

(4)Selective testing: For low-reliability products, use AOI on a portion of the boards instead of all. This can balance cost and risk.

Bill of Materials (BOM) Cost Control

7.4 Partner with One-Stop Manufacturers

Understanding the factors that affect PCB assembly costs is important. However, partnering with the best PCB Assembly vendor will also make a big difference in ensuring quality and timely delivery. Selecting an experienced and reliable PCB assembly manufacturer will help you achieve success.

(1)One-stop Service: You can give priority to high-quality factories that provide both PCB manufacturing and assembly. They can provide high-quality PCB assembly services. Quality can prevent costly rework and repairs as well as product failures in the future.

(2)Regional optimization: For high-volume orders, Chinese factories are preferred. Chinese factories can provide the most cost-effective PCB assembly services. This can significantly reduce costs. Orinew offers cost-effective solutions without compromising quality or standards. We are the ideal partner for PCB assembly because of our commitment to excellence, modern facilities, and experienced team.

For small batches/urgent orders, choose nearby suppliers. This can effectively shorten delivery time and save time costs.

7.5 Cost-Effective Packaging & Shipping

(1)Anti-Static Packaging Standardization: Use generic ESD bags instead of custom trays for non-fragile boards, saving packaging costs.

(2)Economy Shipping for Non-Urgent Orders: Choose sea/rail transport over air freight for bulk orders. This can largely reduce shipping costs.

7.6 Common Pitfalls to Avoid

(1)Underestimating Hidden Costs: It’s easy to ignore hidden costs such as testing, rework, and compliance certification. They are also significant expenses.

(2)Sacrificing Quality for Low Cost: You may choose a low-price supplier to save costs. But this often results in high defect rates, increasing long-term costs.

(3)Poor BOM Management: Wrong or missing component purchases can cause delivery delays. This can also lead to additional shipping costs.

(4)Inefficient Process Selection: Blindly pursue full automation for small batch orders. The cost at this time is much higher than the cost of manual assembly. The mixed process board (SMT+THT) does not optimize the process, resulting in dual-track production line switching losses (2 hours of downtime per day). This will reduce output and increase labor costs.

Common Pitfalls to Avoid

8.PCB Assembly Cost FAQs

9.Summary

PCB assembly cost is influenced by many factors. These include component selection, quantity ordered, complexity of design, process, and geographical location. There is no unified quotation but it can be controlled through DFM optimization and supplier strategy.