OEM or EMS: Which One's Right for You in 2025?

The parts needed for a product may come from many sources. Simple products may only require one supplier to complete the one-stop service, but what about complex ones? To understand which company can meet your needs, you must understand OEM and EMS. This blog will discuss OEM vs. EMS, help you understand what they are, the difference between them, and how you can choose a company representative.

What is an Original Equipment Manufacturer (OEM)?

Do you often hear the word OEM, seem to understand its concept and find it difficult to judge?

Original equipment manufacturers (OEMs) an electronics manufacturers that make the parts that other companies need. They specialize in producing parts, components, or equipment and then sell them to other companies, which assemble them into final products and put their brands on them. However, it is worth noting that different parts of a product may come from multiple OEMs or only from one OEM, depending on the complexity of the product and the integration capabilities of the OEM. If you still have difficulty understanding the concept of OEMs, please look at the following example to understand:

• Brand A designed a superb mobile phone, but they don’t have a factory.
  

• OEM B has advanced production lines and skilled workers.

• Brand A found OEM B and asked B to help them produce this mobile phone.

• OEM B produced the mobile phone according to Brand A's design drawings and requirements, put Brand A's trademark on it, and then gave it to Brand A to sell.

What is EMS?

Electronics Manufacturing Services (EMS) refers to manufacturers that provide a range of services to electronic product brand owners. These services include design, engineering development, raw material procurement and management, manufacturing, testing, and after-sales service.

Sounds confusing? In simple terms, EMS companies produce electronic products for other companies.

For example:

• Brand C wants to make a smartwatch, but it doesn’t have a factory and doesn’t want to worry too much about it.

• EMS manufacturer D has powerful R&D and manufacturing capabilities and can provide a range of services, from design, procurement, and production to testing, packaging, and even after-sales.

• Brand C finds EMS manufacturer D and "packages" the smartwatch project to D.

• EMS manufacturer D helps C to handle all aspects of the watch, and finally C only needs to sell it under the brand name.

In the actual above examples, some EMS manufacturers are responsible for assisting in development (finding errors, optimizing performance, etc.). In contrast, others are responsible for concept research and development to product implementation from beginning to end.

What are Differences between OEM and EMS？

The most apparent difference between OEM and EMS is their R&D strength and production advantages.

R&D Capabilities

OEM manufacturers generally lack R&D capabilities, but EMS can independently develop and design or assist clients in R&D.

Supply Chain Capabilities

OEMs have fixed factory line configurations for production, while EMS can flexibly customize the supply chain. In other words, many EMS manufacturers have their own upstream and downstream supply chains in the industry, which can also more flexibly accept customized demands from various fields.

Pros and Cons

For standard and well-designed projects, OEM manufacturers have the advantage of lower-cost quotes for large-volume orders. However, if you have more complex projects to outsource, some OEMs will not be able to do it due to the fixed equipment and production line configuration so that they will outsource. This will cause two problems. One is that the cost will increase sharply compared to simple projects, and the other is that they lack experience in complex projects, making it difficult to give a satisfactory yield.

If you design a project and give it to an EMS manufacturer for manufacturing, the cost will usually be higher than direct OEM processing. However, EMS has R&D and DFM capabilities and can find defects or improvements in your project design documents. This has great strategic significance for reducing costs and increasing efficiency in the future.

What is the Added-Value of EMS?

Many people still find the concept of EMS's R&D capabilities mentioned above to be rather vague. Therefore, the following three actual cases will illustrate the added value of EMS manufacturers.

 

Case I. High Current Circuit Design and Manufacturing

Project purpose: Testing equipment for electric vehicle battery modules

Requirement: A control board needs to run a high current of 100V DC up to 180 amps, and the customer encountered difficulties in PCB design.

How to transfer current from copper bus to SMT components and back to the copper bus

PCBONLINE Solution:

1. Use copper busbars to replace PCB copper foil design
2. Calculate the size and package design of the copper busbar and provide CAD drawing reference
3. Accurately calculate the size of the copper bar to adapt to SMT patch production, improve production efficiency and reduce defective rate (the size of the copper bar is too large and will deform under the high temperature of wave soldering)
4. It is recommended to use a multi-channel Mosfet design to shunt the voltage (Opposite magnetic Mosfet can also be customized according to the application scenario to realize two different module networks of high voltage and low voltage);

The final design is as follows:

With the assistance of PCBONLINE engineers, the customer completed the PCB design and commissioned the PCBONLINE factory to complete sample production and verify that the sample was successful at one time. Now, it has been successfully mass-produced. During the entire early R&D process, PCBONLINE provided free technical support, which helped save R&D costs and valuable time.

Case II. Reduce the cost of IOT motherboard

Project purpose: IOT Motherboard for E-scooter

PCBONLINE did not participate in the project's initial R&D, but we helped customers solve the following problems during the free DFM process before production: avoiding costs caused by customer design defects and reducing component procurement costs by at least 10%.

1. During the pre-production DFM process, PCBONLINE engineers discovered that the shield cover designed by the client was a patch-covering type, which would prevent the components under the shield cover from undergoing AOI and X-RAY inspections after SMT was completed. Therefore, we suggested that the client change to a snap-on shield cover so that the shield cover could be covered after AOI and X-RAY were completed. The client agreed to our suggestion.

2. DFM check before production: Engineers found that the BOM specification descriptions of three models of passive components were different from the pad packages of the PCB design. We reminded the customer to check this issue, and the customer eventually modified the PCB pad and circuit design to resolve this potential risk;

3. Since PCBONLINE purchases components in a centralized manner, brands and agents give us great price support, especially for the communication modules of IOT products (such as: Espresif, Neoway, Quectel, we have direct strategic cooperation with the original manufacturers). We have a great price advantage. Customers told us that it saves them 15% of component procurement costs.

Should I choose OEM or EMS?

This depends on many factors, such as whether the company has an R&D team, whether the project at hand requires assistance in development, and whether the company is a mature enterprise or a startup. The following analysis from multiple angles is for your reference:

Reasons for choosing OEM

• Confidence in your design: If you have a complete product design plan and technical team, OEM can focus on production.

• Cost sensitivity: With a limited budget, only the manufacturing process needs to be solved, and OEM costs are lower.

• Intellectual property protection: Hope to fully control the design and core technology to avoid technology leakage.

• Large-volume stable orders: The demand is apparent, the scale is significant, and OEM is suitable for long-term and stable cooperation.

Reasons to choose EMS

• Lack of R&D capabilities: suppliers are required to participate in design optimization, component selection, and other technical support.

• High product complexity: For products involving electronics, software, and supply chain integration (such as smart hardware), EMS can provide a one-stop service.

• Fast time to market: EMS can shorten the cycle from design to mass production and seize market opportunities.

• Small batch trial production or flexible production: flexible adjustment of production capacity or customized production is required.

If your strengths are brand and design, choose OEM; if your strengths are market and channels, choose EMS to relieve manufacturing pressure.

Industry perspective:
Highly complex fields such as medical devices tend to be EMS;
Standardized products such as simple consumer hardware: OEM is more efficient.

R&D perspective:
EMS has R&D capabilities and will continue to update, and iterate R&D capabilities so that it can keep up with customer needs in the future
OEM generally does not have R&D capabilities.

In short, start-ups can consider EMS, which operates at a low cost (there is no need to hire an R&D team) and focuses on market verification. For mature companies, choosing OEM can help them reduce costs and increase efficiency. Of course, the choice should be based on the business stage, product characteristics, and long-term strategy. A hybrid model can also be adopted (part of the process is outsourced to EMS, and OEM completes the rest).

One-Stop HDI PCB Manufacturer and Its PCB Via Filing Capabilities

If you're looking for turnkey HDI electronics manufacturing services (EMS) from hardware development to PCBA fabrication and box-build assembly, you can work with the one-stop HDI PCBA manufacturer PCBONLINE.

Founded in 1999, PCBONLINE has R&D capabilities for HDI projects and EMS manufacturing capabilities, including via filling for stacked vias. It provides 4-to-64-layer HDI PCB fabrication, assembly, and PCBA box-build assembly. You can order various HDI PCBs from PCBONLINE, such as FR4, polyimide (flexible PCB), polyimide + FR4 (rigid-flex PCB), and PTFE/Rogers (high-frequency PCB).

Here'e the PCB via filing capabilities at PCBONLINEL:

• Micriavia filling with copper: laser via size 0.1-0.125mm, priority 0.1mm
• Finished hole size for via-in-pad filling with resin: 0.1-0.9mm (drill size 0.15-1.0mm), 0.3-0.55mm normal (drill size 0.4-0.65mm)
• Max aspect ratio for via-in-pad filling with resin PCB - 12: 1
• Min resin plugged PCB thickness: 0.2mm
• Max via-filling ith resin PCB thickness: 3.2mm
• Making different hole sizes with via filling in one board: Yes
• Via filling with copper/silver: Yes

If you need HDI PCBAs or any other PCBAs requiring via filling, please send your email to PCBONLINE at info@pcbonline.com. We will provide one-on-one engineering support to you.

Conclusion

Via filling is used for creating stacked vias in HDI PCB fabrication, BGA/CSP/QFN IC packaging, and filling PCB via-in-pad with resin during multilayer PCB fabrication. If you need one-stop electronics manufacturing for your HDI PCBA project, contact the one-stop advanced PCB manufacturer PCBONLINE for high-quality PCBA and box-build solutions tailored to your project's needs.