What Size Split Shot for Trout? Size and When To Use Them

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Package of Split Shot

Most trout anglers stick with split shots that range from BB to size 3. The lower the number, the heavier the split shot. It takes time to understand what size split shot you want, so study how your fly drifts before you choose.

In the world of fly fishing, the use of split shots is controversial. The first question you often get when you say you’re using split shot for trout is, “Why?” Many trout anglers use multi-nymph rigs or work hard to use flows to get their flies at the necessary depth. However, there are times when split shots are a necessity.

What Split Shot Sizes Are Best? 

The proper size split shot depends on the flow rate, the weight of your fly, and where you want it sitting in the water column. To check this, cast upstream and watch your fly drift downstream. Look closely at where it sits in the water column. Does it disappear towards the bottom? Does it sit right near the surface? 

A split shot might be helpful if you want it lower and it stays near the surface. If it immediately drops, there’s likely no need for one. Understand that depending on the weight of your split shot, it’ll immediately pull it below the surface, so if you don’t want it all the way at the bottom, use a lighter one. 

Trout often want to eat food that’s directly above them, so don’t feel as if you need it bouncing at the bottom. 

Size 3 (Furthest on the Right)
Size 3 (Furthest on the Right)

Size 3

A size three split shot weighs 1/10 of an ounce. These are a good choice for fishing fast-moving water or deep pools with trout feeding near the bottom. If you’ve fished in these conditions, you understand how hard it is to get your fly near the bottom with a light fly. Whether your fly doesn’t have a beadhead or is not heavy enough, you don’t want a rig that’s getting nowhere near the fish. 

Use a size 3 for those fast currents, extremely deep runs, or deep sections of lakes. You may have to use multiple split shots to get your fly near the bottom. I know I’m in the right place if I get snagged or feel the bumps of rocks and debris. 

You can always add more split shots, so start with fewer and then add as needed. 

Obviously, you should use splitshots with nymphs and streamers. Dry flies must sit on the surface, so make sure you don’t make this mistake. 

Size 5 Split Shot
Size 5 Split Shot

Size 5

Size 5 split shots are lighter than size 3 split shots and weigh 1/13 ounce. I like to use these in medium-sized rivers if I’m fishing with a non-beadhead nymph or light streamer. I mainly fish with nymph rigs or try to achieve a better drift, but some pools or seams drop in depth, so suddenly, a split shot is necessary. 

I’ll cast just above the deep run or pool and let my fly drop into the deep water as quickly as possible. I usually start with one size 5 split shot before adding others. Thankfully, most split shots are easy to remove, so if they aren’t necessary, I’ll remove them, and they don’t cause any damage. 

Size 4 Split Shot
Size 4 Split Shot

Size 3/0 Split Shot

Size 3/0 split shots are much smaller than size 5 split shots, weighing 1/50 of an ounce. These are some of the most common split shots I use. These lead weights are plenty in small rivers, lakes, and medium-sized rivers. I like them because they’re smaller and don’t stand out as much as some of the larger split shots recommended. 

Size 2 Split Shot
Size 2 Split Shot

Size BB Split Shot

Size BB split shot weight 1/64 ounce. Most fly anglers choose between these or the size B splitshot (1/96 ounce). These are extremely small and do the trick on small rivers, streams, and relatively deep water. Again, add more split shots if needed, but start with one and see how your fly drifts. 

Feel the bounces along the bottom before adding more split shots. I’ve found that BB split shots work well when trying to keep my flies more in the middle of the water column. It’s tough to keep flies mid-column, so these tiny split shots work wonders to keep your drifts more consistent. 

Beadhead Fly
Beadhead Fly

When To Use Split Shot

Danny standing on the rock, fishing in the river.

As mentioned, you want to use split shots when struggling to keep your flies at a consistent depth. When you where fish are feeding, you want to keep your flies there as much as possible. Split shots do the trick in keeping your fly in the same spot cast after cast. 

The current is always faster near the water’s surface, so keep that in mind as you choose the size of your split shot. Doing a test drift near you before selecting your split shot size is the best way to understand the best option. 

If I’m not getting any action on my flies and nothing is working, I often attach a split shot. My flies aren’t getting deep enough, especially when fishing in the middle of the day. 

Don’t feel ashamed if you’re using a split shot. There’s nothing wrong with them; when used properly, they’ll help you land more fish. I almost always use split shots when I’m fishing nymphs. I rarely use them when using streamers, only when the flies have no bead heads, or it’s extremely fast or deep water. 

Split Shot vs. Beadhead Fly 

If you’re the type who wants more flies in the water, you can create a nymph rig instead of using a split shot. Attaching a heavy lead fly and lighter trail flies is a good choice. The extra weight gets your flies lower in the water column, so you may not have to use a split shot. 

I like the nymph rigs instead of split shots, but there are always exceptions, and different conditions require different methods. I’ve paired nymph rigs with small split shots when fishing big rivers during runoff season or extra high flows. 

My favorite nymph rig includes a size 16 pheasant tail, a size 18 RS2, and a San Juan Worm at the back. It’s a killer trout setup that works everywhere I target trout. 

Split Shot
Split Shot

Frequently Asked Questions 

Where Should I Put Split Shot on My Line? 

I’ll attach the split shot on my leader from 8 to 12 inches above my nymphs. Even if I’m fishing a nymph rig, I’ll keep the split shot above my flies because I want the trailing nymphs to drift as naturally as possible. 

How Many Split Shots Do I Use? 

Always start by fishing with one fly, and then you can add more if your flies aren’t getting deep enough. You don’t want to blow up a hole with a poor drift, so start light and get heavier. 

Are Split Shots Safe to Use?

Yes, split shots are safe and legal to use in almost every body of water. Certain fisheries don’t allow the use of split shots, so make sure you do some checking before you use them. 

How Do I Cast With Split Shots?

Fly anglers are well aware of how frustrating it can get to cast with split shots on your leader. A poor cast can tangle your flies and split shots, requiring a 20-minute untangling session. I always cast slow when fishing a nymph rig or with split shots. Quick false casts almost always result in a tangle. Let your line unfurl, and attempt to make as few false casts as possible. 


Split shots are a valuable tool for fly fishing. They’ll add that final touch you might need to get to a stubborn fish. Always carry a few different sizes in your pack if you find a pool or unreachable seam without that extra weight. Sizes BB through size five work well for most fly fishing adventures. 

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