How To Find the Perfect Bead Size For Every Fly

Beads not only add weight to help your fly sink but also enhance its appearance and realism. Once you understand how different bead sizes affect fly performance, you can improve your fly fishing success.

Whether you're tying delicate midges or heavy nymphs for fast-moving water, our fly tying bead size chart will help you choose the perfect bead for each fly pattern.


How Bead Size Affects Fly Performance


  • The relationship between bead size and hook size: Larger beads require hooks with bigger gapes to maintain a proper keeling and balance, while smaller beads work best on fine-wire hooks for delicate patterns.
  • How different bead sizes influence a fly’s sink rate: Heavier tungsten beads sink faster, making them ideal for deep nymphing, while brass and glass beads provide a slower descent for fishing in shallower waters.
  • When to use smaller vs. larger beads based on fishing conditions: Small beads are effective in clear, slow-moving water where fish are more cautious. Larger beads excel in fast currents where a quick sink rate is necessary to reach feeding zones.

Matching Beads to Fly Patterns


Midges & small nymphs: Use 1.5mm-2.4mm beads for size 18-22 hooks.

Standard nymphs (Pheasant Tail, Hare’s Ear, etc.): 2.4mm-3.5mm beads for size 12-16 hooks.

Streamers & large nymphs: 3.5mm-5mm beads for size 6-10 hooks.


Standard Fly Tying Bead Size Chart


Bead Size (mm)

Common Hook Sizes

Fly Patterns

Material Options

1.5mm (1/16")

18-22

Midges, Small Nymphs

Brass, Glass

2.0mm (5/64")

16-20

Small Nymphs, Micro Streamers

Brass, Glass

2.4mm (3/32")

14-18

Standard Nymphs (Pheasant Tail, Hare’s Ear)

Brass, Tungsten

2.8mm (7/64")

12-16

Larger Nymphs, Small Streamers

Brass, Tungsten

3.2mm (1/8")

10-14

Medium Nymphs, Large Pupa, Jig Flies

Brass, Tungsten

3.8mm (5/32")

6-12

Large Nymphs, Small Streamers

Brass, Tungsten

4.6mm (3/16")

4-8

Streamers, Large Nymphs

Tungsten

5.5mm (7/32")

2-6

Large Streamers, Heavy Nymphs

Tungsten

Tungsten Bead Size Chart


Tungsten Bead Size (mm)

Common Hook Sizes

Fly Patterns

Best Use Case

2.0mm

16-20

Small Nymphs, Midges

Slow to moderate water, shallow depths

2.4mm

14-18

Standard Nymphs

General use, moderate depths

2.8mm

12-16

Heavier Nymphs, Perdigons

Faster currents, deeper pools

3.2mm

10-14

Jig Nymphs, Large Nymphs

Heavy flows, deep water

3.8mm

6-12

Small Streamers, Large Nymphs

Deep holes, fast-moving rivers

4.6mm+

4-8

Large Streamers, Euro Nymphs

Heavyweight flies for deep runs




Why Choose Tungsten?

  • Denser than brass – Sinks flies faster with less bulk.

  • Best for euro nymphing and deep-water presentations.

  • Maintains a compact profile while increasing sink rate. 

Whether you’re dialing in a winter midge or rigging up a heavy dropper for spring runoff, getting the bead size right can mean the difference between a quick take and a quiet day. Use this guide as your go-to reference, and don’t be afraid to experiment—because sometimes the perfect bead isn't just about the numbers, but how the fly moves in the water. Need to stock up or try something new? Explore our full range of beads and start tying with precision.

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