ITOT vs SOXX: how much do they really overlap?
ITOT (iShares Core S&P Total US Stock Market ETF, tracking the S&P Total Market) and SOXX (iShares Semiconductor ETF, tracking the NYSE Semiconductor) overlap by roughly 28% by weight. 3 of ITOT's top 10 holdings also appear in SOXX. A 50/50 blend of the two behaves like about 47 equally-weighted bets (diversification grade B). In short, the two funds share a meaningful core of the same megacaps, but each also brings real exposure the other lacks.
The same companies, in both funds
These 10 holdings appear in both ITOT and SOXX. The weight columns show how much of each fund each name represents.
| Holding | in ITOT | in SOXX |
|---|---|---|
| NVDA NVIDIA CORP | 6.63% | 6.81% |
| AVGO BROADCOM INC | 2.45% | 6.08% |
| MU MICRON TECHNOLOGY INC | 1.78% | 8.54% |
| AMD ADVANCED MICRO DEVICES INC | 1.30% | 8.09% |
| INTC INTEL CORPORATION | 0.90% | 6.33% |
| AMAT APPLIED MATERIAL INC | 0.78% | 5.77% |
| LRCX LAM RESEARCH CORP | 0.74% | 4.89% |
| KLAC KLA CORP | 0.54% | 5.64% |
| TXN TEXAS INSTRUMENT INC | 0.37% | 3.50% |
| MRVL MARVELL TECHNOLOGY INC | 0.36% | 4.88% |
Only in ITOT
iShares Core S&P Total US Stock Market ETF — total US market. Its biggest holdings that SOXX doesn’t have:
| AAPL APPLE INC | 5.81% |
| MSFT MICROSOFT CORP | 3.79% |
| AMZN AMAZON.COM INC | 3.19% |
| GOOGL ALPHABET INC CLASS A | 2.86% |
| GOOG ALPHABET INC CLASS C | 2.29% |
| META META PLATFORMS INC CLASS A | 1.69% |
| TSLA TESLA INC | 1.62% |
| LLY ELI LILLY | 1.30% |
Only in SOXX
iShares Semiconductor ETF — semiconductors. Its biggest holdings that ITOT doesn’t have:
| TSM TAIWAN SEMICONDUCTOR MANUFACTURING | 4.26% |
| ADI ANALOG DEVICES INC | 3.45% |
| TER TERADYNE INC | 3.36% |
| NXPI NXP SEMICONDUCTORS NV | 3.14% |
| ALAB ASTERA LABS INC | 3.02% |
| MPWR MONOLITHIC POWER SYSTEMS INC | 2.93% |
| QCOM QUALCOMM INC | 2.65% |
| ASML ASML HOLDING ADR REPRESENTING NV | 2.30% |
So — partly overlapping. Should you hold both?
ITOT and SOXX share a meaningful core of the same megacaps, but each also brings real exposure the other lacks. Held together they keep a shared megacap core but each still pulls in exposure the other lacks, so a 50/50 blend spreads to ~47 effective positions (grade B).
Holdings as of — ITOT: Jun 30, 2026 (iShares (BlackRock)); SOXX: Jun 30, 2026 (iShares (BlackRock)). Refreshed monthly. Overlap is measured across each fund’s largest holdings (top 50); the diffuse long tail barely moves the math.
See this for YOUR whole portfolio, free →ITOT vs SOXX — FAQ
- How much do ITOT and SOXX overlap?
- ITOT and SOXX overlap by approximately 28% measured by portfolio weight — that is the share of the smaller fund's holdings (by weight) that also sit inside the other. 3 of ITOT's 10 largest holdings are also held by SOXX. They share 10 of their listed top holdings in total.
- Is it redundant to hold both ITOT and SOXX?
- Because they share a meaningful core of the same megacaps, but each also brings real exposure the other lacks, holding both is partly redundant: you double up on a shared core (NVDA) while each fund still adds distinct exposure. A 50/50 blend has an effective 47 positions and a B diversification grade.
- What does SOXX hold that ITOT doesn't?
- SOXX's largest holdings that ITOT doesn't hold include TSM, ADI, TER, NXPI, ALAB. Its category is semiconductors, versus ITOT's total US market.
- Which is more concentrated, ITOT or SOXX?
- ITOT's top 10 holdings are 58% of its listed weight; SOXX's are 61%. The more concentrated fund leans harder on its largest names.