Choosing between Surface Mount Device (SMD) LEDs and Through-Hole LEDs (TH LEDs) depends on your application, manufacturing process, and performance requirements. While SMD LEDs dominate modern lighting products, through-hole LEDs remain popular for indicators, hobby electronics, and applications requiring mechanical strength.

This guide compares both technologies to help engineers, buyers, and product designers select the right LED solution.

What Is an SMD LED?

An SMD LED is a surface-mounted light-emitting diode that is soldered directly onto the surface of a printed circuit board (PCB). It has no long leads, making it compact and suitable for automated assembly.

Popular SMD LED packages include:

• 2835 LED

• 3030 LED

• 3535 LED

• 5050 LED

• 5630 LED

SMD LEDs are widely used in:

• LED bulbs

• Street lights

• Flood lights

• Grow lights

• Automotive lighting

• Commercial lighting

• LED strips

Advantages of SMD LEDs

• High luminous efficiency

• Compact package size

• Excellent thermal performance

• Supports automated SMT production

• High packing density

• Available in white, RGB, UV, IR, and custom wavelengths

• Suitable for high-power applications

What Is a Through-Hole LED?

A Through-Hole LED features two wire leads that pass through holes in the PCB and are soldered on the opposite side.

Common sizes include:

• 3 mm LED

• 5 mm LED

• 8 mm LED

• 10 mm LED

These LEDs are commonly found in:

• Indicator lights

• Electronic instruments

• DIY electronics

• Educational kits

• Decorative displays

• Simple control panels

Advantages of Through-Hole LEDs

• Easy to hand solder

• Strong mechanical attachment

• Low manufacturing cost for small quantities

• Wide viewing angles available

• Ideal for prototyping

SMD LED vs. Through-Hole LED Comparison

Brightness Comparison

Modern SMD LEDs produce significantly more light than traditional through-hole LEDs.

Examples include:

• 2835 SMD LED: up to 220 lm/W

• 3030 SMD LED: commonly used in street lighting with high efficacy

• 3535 SMD LED: ideal for high-power outdoor lighting

• 5050 SMD LED: supports RGB and RGBW lighting

Traditional 5 mm through-hole LEDs typically produce only a few lumens, making them suitable mainly for status indication rather than illumination.

Heat Dissipation

Thermal management is one of the biggest advantages of SMD LEDs.

SMD LED

• Large thermal pad

• Direct contact with MCPCB or aluminum PCB

• Supports high current operation

• Better lumen maintenance

Through-Hole LED

• Heat dissipates mainly through the leads

• Limited power handling

• Not suitable for high-power lighting

Manufacturing Differences

SMD Production

• Fully automated SMT placement

• Reflow soldering

• High production efficiency

• Excellent consistency

Through-Hole Production

• Manual insertion or insertion machines

• Wave soldering

• More labor intensive

• Lower production speed

For large-scale LED lighting manufacturing, SMD technology is the industry standard.

Application Comparison

SMD LEDs are best for:

• LED street lights

• Flood lights

• High bay lighting

• Solar lighting

• Grow lights

• Automotive headlights

• Smart lighting

• Commercial lighting

• Industrial lighting

• LED modules

Through-Hole LEDs are best for:

• Power indicators

• Signal lamps

• Consumer electronics

• DIY projects

• Educational electronics

• Electronic toys

• Simple display boards

Reliability

SMD LEDs generally offer:

• Better vibration resistance

• Higher thermal stability

• Improved lumen maintenance

• Longer service life under high-power operation

Through-hole LEDs remain reliable for low-power electronic applications but are less suitable for demanding lighting environments.

Which One Should You Choose?

Choose SMD LEDs if you need:

• High brightness

• High efficiency

• Compact designs

• Automated production

• Long lifespan

• High-power lighting

Choose Through-Hole LEDs if you need:

• Easy manual assembly

• Simple indicator lighting

• Low-volume production

• Educational or hobby projects

• Strong mechanical anchoring

SMD LEDs have become the preferred choice for modern lighting because they deliver superior efficiency, higher brightness, better thermal management, and lower manufacturing costs in high-volume production. Packages such as 2835, 3030, 3535, and 5050 are now widely used in commercial, industrial, automotive, and horticultural lighting.

Through-hole LEDs, however, still have an important place in electronics. Their ease of hand assembly, durability, and low cost make them ideal for indicator lights, prototypes, educational kits, and small electronic devices.

For most professional lighting applications, SMD LEDs are the clear winner, while through-hole LEDs continue to serve niche applications where simplicity and mechanical strength are the primary requirements.