Where to find cheap SMD ferrite beads?

Generally, SMD ferrites of a given size are characterized by:

• The RF impedance (typically specified @100 MHz)
  • Low impedance (e.g. 100 Ω @ 100 MHz) do not filter EMI that well, but also distort your data signals less. Use them for high speed signals above 1 MHz
  • High impedance ferrites, e.g. 1kΩ @ 100 MHz, filter EMI really well but will distort any high speed signal. Use them for low speed signals below 1 MHz
• The current rating
  • For data signals, you don’t need any form of high current rating. Generally, I would recommend to require at least 0.1A of current rating to be able to handle soft short circuits
  • For power lines, use whatever power rating is suitable (the specified current + 20% is typically fine)
• The DC resistance. This mostly only matters for power lines.
  • Keep in mind to keep the ferrite cool by choosing the DC resistance so that the

As with most passive parts, LCSC generally has the lowest pricing if you buy a bunch of parts.

Keep in mind the expensive shipping, but since they are often 50 times cheaper (!) than other distributors, it might be worth it even if just ordering a reel of ferrites.

Signal ferrites

This section contains cheap SMD ferrite beads for < 1A current rating.

Low impedance (<= 500Ω):

• LCSC 0603 100Ω 200mA CBG160808U101T @ 0.0019€/pc@4000pc = 7.60€/reel

High impedance (>= 500Ω):

• LCSC 0805 600Ω 300mA CBG201209U601T @ 0.0026€/pc@4000pcs = 10.40€/reel
• LCSC 0603 1kΩ 400mA FCM1608KF-102T04 @ 0.0027€/pc@4000pc = 10.80€/reel
• LCSC 0805 1kΩ 800mA CBW201209U102T @ 0.0044€/pc@4000pc = 17.60€/reel
• DigiKey 0603 1kΩ 400mA 2506031027Y0 @ 0.01264€/pc@4000pc = 50.56€/reel
• TME 0805 1kΩ 200mA LCCB-102 @ 0.0181€/pc = 72.40€/reel

Power ferrites

This section contains cheap SMD ferrite beads for > 1A current rating.

Low impedance (<= 500Ω):

• LCSC 1206 120Ω 3A CBW321609U122T @ 0.006€/pc@4000pc = 24. 00€/reel
• LCSC 1206 120Ω 4A CBM321609U121T @ 0.0086€/pc@4000pc = 34.40€/reel

High impedance (>= 500Ω):

• LCSC 1206 1.2kΩ 1A CBW321609U122T @ 0.0088€/pc@4000pc = 35.20€/reel
• LCSC 1206 1kΩ 2A CBW321609U102T @ 0.0095€/pc@4000pc = 38.00€/reel