IWM vs RESM
iShares Russell 2000 ETF vs Columbia Research Enhanced Small Cap ETF
Which is better, IWM or RESM?
IWM costs less.
IWM has a lower expense ratio. IWM is less concentrated, with 3.5% of the fund in its ten largest positions against 76.5%.
MarketXLS is not an investment adviser. This comparison is generated automatically from market data and is for information only. A Best mark means the better reading on that one measure, not a recommendation to buy.
Side-by-Side Comparison
| Metric | IWM | RESM |
|---|---|---|
| Expense Ratio | 0.19%Best | 0.32% |
| AUM | $76.0B | $6M |
| Dividend Yield | 0.98% | 0.08% |
| Holdings | 1,972 | 2,051 |
| YTD Return | +9.82% | +13.69%Best |
| 1Y Return | +10.58% | - |
| 3Y Return (annualized) | +17.51% | - |
| 5Y Return (annualized) | +5.03% | - |
| Top 10 Weight | 3.5%Best | 76.5% |
| Fund Family | iShares by BlackRock (US) | Columbia Threadneedle Investments |
| Category | Equity | Equity |
| Style | Small Cap Blend | Small Cap Blend |
| Inception | May 22, 2000 | Dec 11, 2025 |
Not shown on this pair: Volatility (annualized), Max Drawdown, $10,000 over the window.
IWM vs RESM growth
Month-end closes. Both lines start at 0% in the first month shown, so the gap between them is the difference in growth across that window. The full view is available from the range buttons; it is not the opening view here because over the whole period one of these two funds moves so much further than the other that its line would sit flat on the axis.
IWM vs RESM Performance
iShares Russell 2000 ETF (IWM) is an ETF from iShares by BlackRock (US) and Columbia Research Enhanced Small Cap ETF (RESM) is an ETF from Columbia Threadneedle Investments. Year to date, IWM is up 9.82% versus a gain of 13.69% for RESM.
Past performance does not guarantee future results.
Fees and Cost Over Time
IWM charges 0.19% per year while RESM charges 0.32%. On a $10,000 position that is $19 vs $32 annually, a gap of $13 per year that compounds over a long holding period. On income, IWM currently yields 0.98% against 0.08% for RESM.
Holdings Overlap
0.1% of IWM's money is in holdings RESM also owns. 3.7% of RESM's money is in holdings IWM also owns.
RESM and IWM share little of their money.
3 positions in common, counted across the 1,973 positions we hold weights for in IWM and 25 in RESM, against full books of 1,972 and 2,051.
What only one of them owns
Our book lists 4 positions for RESM that do not appear in our book for IWM (24.0% of the fund), and 1,689 for IWM that do not appear in RESM (96.1%).
Some of those will be the same company recorded under a different code in one of the two books, so the real difference in what you would own is no larger than this and may be smaller. We do not name the individual positions here for that reason.
You are not choosing between two funds in isolation.
Whichever of IWM and RESM you pick has to sit alongside everything else you own. Add the rest and see what the combination actually holds.
Free for up to 10 holdings. No account needed.
Frequently Asked Questions
Which is cheaper, IWM or RESM?
IWM has an expense ratio of 0.19% while RESM charges 0.32%. IWM is the cheaper option, by $13 a year on a $10,000 investment.
What is the holdings overlap between IWM and RESM?
3.7% of RESM's money is in holdings IWM also owns. 3.7% of RESM's is in holdings IWM also owns. They hold 3 positions in common, counted across the 1,973 positions we hold weights for in IWM and 25 in RESM.
Which pays a higher dividend, IWM or RESM?
IWM yields 0.98% while RESM yields 0.08%, so IWM currently pays the higher dividend yield.
Is RESM better than IWM?
IWM has a lower expense ratio. IWM is less concentrated, with 3.5% of the fund in its ten largest positions against 76.5%. Which one suits a particular account depends on what it is for. This is information, not a recommendation.