What Is IWM? iShares Russell 2000 ETF
Short answer
IWM is the iShares Russell 2000 ETF, a fund that tracks the Russell 2000 small-cap index at a 0.19% expense ratio. It holds roughly 2,000 smaller US companies, so it is far more diversified across the small-cap market and much less tech-concentrated than VOO. Versus a large-cap fund, IWM gives exposure to the small-cap segment, which is more domestically focused and historically more volatile.
What does IWM hold? (top 10)
Approximate weights as of early 2026; refresh quarterly from the issuer's fund page. Tickers link to the individual stock guide in Walnut.
| Rank | Ticker | Company | % of IWM | |
|---|---|---|---|---|
| 1 | IWM | Small-cap constituents are broadly diversified | <1% each | |
| 2 | FTAI | FTAI Aviation | ~0.6% | |
| 3 | SFM | Sprouts Farmers Market | ~0.5% | |
| 4 | INSM | Insmed | ~0.5% | |
| 5 | VKTX | Viking Therapeutics | ~0.4% | |
| 6 | FIX | Comfort Systems USA | ~0.4% | |
| 7 | MLI | Mueller Industries | ~0.4% | |
| 8 | ANF | Abercrombie & Fitch | ~0.3% | |
| 9 | CVLT | Commvault Systems | ~0.3% | |
| 10 | SSD | Simpson Manufacturing | ~0.3% |
The bottom line on IWM
IWM is the standard way to add US small-cap exposure in one ticker, complementing rather than replacing a large-cap core like VOO. It is more volatile and more sensitive to the domestic economy and interest rates, so it tends to function as a diversifying sleeve sized around a broad core.
Build a portfolio around IWM with Walnut
Use IWM as your core holding, then let Walnut's AI propose thematic satellites: AI infrastructure, dividend growth, clean energy, whatever you believe in. Connect your broker, build the basket in conversation, track it as one unit.
FAQ
What is IWM?
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IWM is the iShares Russell 2000 ETF, a single ticker that holds roughly 2,000 smaller US companies. It tracks the Russell 2000, the standard small-cap benchmark, so it captures the small-cap segment of the US market rather than the large-caps that dominate VOO or QQQ.
What is IWM's expense ratio?
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0.19% per year (19 basis points) as of early 2026. On a $10,000 investment, that is about $19 per year in fees, higher than broad large-cap funds because the small-cap index has more holdings and turnover. Verify the current figure on the iShares site.
IWM vs VOO: what's the difference?
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VOO holds the S&P 500, roughly 500 US large-caps. IWM holds the Russell 2000, roughly 2,000 US small-caps. They cover different ends of the market and complement each other rather than overlap. IWM is more domestically focused, more diversified across names, and historically more volatile. Walnut is not an investment adviser, so this is not a recommendation.
Does IWM pay a dividend?
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Yes, quarterly. The trailing yield is approximately 1.2% as of early 2026, drawn from the dividends of the underlying small-cap companies. Many small-caps pay little or no dividend, so the yield is modest.
What companies are in IWM?
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Roughly 2,000 small-cap US companies, with no single name dominating; the largest positions are typically under 1% each. Holdings rotate as companies grow into mid-caps or are added to the index. Top names change frequently, so verify the current list on the issuer's site.
Why is IWM more volatile than large-cap funds?
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Small-cap companies are smaller, less liquid, more leveraged on average, and more sensitive to the domestic economy and interest rates than large-caps. As a result the Russell 2000, and IWM with it, tends to swing more in both directions than the S&P 500.
IWM vs IJR: what's the difference?
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Both are small-cap ETFs from iShares. IWM tracks the Russell 2000; IJR tracks the S&P SmallCap 600, which screens for profitability. IJR's index requirement of positive earnings has historically made it less volatile, and IJR's expense ratio is lower. The two cover similar but not identical universes.
What is IWM's AUM?
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Approximately $70 billion as of early 2026, which makes it one of the largest and most-traded small-cap ETFs. The exact figure moves with markets and flows, so verify on the iShares site.
When was IWM created?
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May 2000. IWM is the most widely traded vehicle for US small-cap exposure and has a deep options market used by traders and hedgers, similar to SPY for large-caps.
How do I buy IWM?
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IWM trades like any stock during US market hours. Buy it through any broker: Robinhood, Fidelity, Schwab, Public, M1, or others. Fractional shares are supported at most modern brokers. Connect your broker to Walnut and the AI can show how a small-cap sleeve like IWM fits with your large-cap core.
Is IWM a good investment?
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IWM adds US small-cap exposure that complements a large-cap core, but it is more volatile and more economically sensitive. Whether it fits depends on your time horizon, what else you own, and how much small-cap exposure you want. Walnut is not an investment adviser, so this is not a recommendation.
Related ETFs
Walnut is informational, not investment advice. Holdings weights and fund statistics on this page are approximations stamped to early 2026; verify current figures against iShares (BlackRock)'s fund page or your broker before investing.