IWF vs SPLG: 57% overlap
iShares Russell 1000 Growth ETF and SPDR Portfolio S&P 500 ETF (now SPYM) share 56.9% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
You would hold two tickers and get the diversification of 1.4. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
IWF and SPLG hold 178 of the same securities. The ten contributing most to the overlap figure:
| Holding | in IWF | in SPLG | Δ |
|---|---|---|---|
| NVDA | 15.1% | 7.9% | 7.2% |
| AAPL | 7.8% | 7.4% | 0.4% |
| MSFT | 4.4% | 4.4% | 0.0% |
| GOOGL | 5.7% | 2.9% | 2.8% |
| AVGO | 5.7% | 2.9% | 2.8% |
| GOOG | 4.7% | 2.4% | 2.3% |
| META | 3.4% | 2.1% | 1.3% |
| MU | 3.5% | 1.8% | 1.7% |
| LLY | 2.9% | 1.5% | 1.5% |
| TSLA | 2.9% | 1.4% | 1.5% |
Where IWF and SPLG differ
Sector weights as a share of each fund, ordered by the size of the gap rather than the size of the sector — two funds that overlap heavily still usually diverge somewhere.
| Sector | IWF | SPLG | Δ |
|---|---|---|---|
| Information Technology | 55.0% | 37.5% | +17.5pp |
| Financials | 4.7% | 12.4% | −7.7pp |
| Communication Services | 15.7% | 9.3% | +6.4pp |
| Health Care | 5.6% | 9.1% | −3.5pp |
| Consumer Staples | 1.3% | 4.6% | −3.3pp |
| Energy | 0.5% | 3.4% | −2.9pp |
| Utilities | 0.3% | 2.3% | −1.9pp |
| Materials | 0.3% | 1.8% | −1.6pp |
Δ is IWF minus SPLG, in percentage points. Sector data is not published by every issuer, so “Unclassified” is a real category rather than a gap in the table.
What each fund holds alone
6.1% of IWF by weight, held in no part of SPLG.
33.6% of SPLG by weight, held in no part of IWF.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| IWF | SPLG | |
|---|---|---|
| Top 10 holdings | 56.1% | 36.9% |
| Positions held | 370 | 507 |
| Cost per $10,000 held, per year | $19 | $2 |
Cost is the expense ratio applied to $10,000; it excludes any brokerage commission, bid-ask spread or tax consequence. Figures are facts about the funds, not a suggestion about which to hold.
Frequently asked
How much do IWF and SPLG overlap?
IWF and SPLG overlap 56.9% by portfolio weight — substantial duplication if you hold both. They share 178 holdings. The figure comes from current issuer holdings files (IWF as of 2026-07-23, SPLG as of 2026-07-23).
How is the overlap between IWF and SPLG calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If IWF holds a stock at 6% and SPLG holds the same stock at 4%, 4% counts as shared. The result is bounded between 0% and 100%, and it is computed after looking through any fund-of-funds to the underlying holdings.
Is it redundant to hold both IWF and SPLG?
That depends on your goals — we state facts, not advice. At 56.9% overlap, each fund still contributes meaningfully distinct exposure.
What does IWF own that SPLG doesn't?
IWF holds 370 positions and SPLG holds 507; 191 of IWF's positions don't appear in SPLG at all, and they are 6.1% of IWF by weight.
You probably hold more than two funds
This page compares IWF and SPLG. Paste your whole portfolio — brokerage, 401(k), IRA — and see the overlap across every fund at once, plus what you actually own underneath them and your own Effective Funds number. Free, no account, nothing stored.
X-ray my portfolio — free →Watch IWF vs SPLG
We re-read both funds’ published holdings every weeknight. Leave an address and we'll tell you when what's inside actually changes.
Not sending yet — email alerts are built but switched off, and you'll be among the first when they turn on. No spam, one-click unsubscribe.
Related comparisons
Sources: issuer holdings files, IWF as of 2026-07-23, SPLG as of 2026-07-23. Weights are fractions of each fund. Diagnostics, not advice.