DIA vs ITOT: how much do they really overlap?
DIA (SPDR Dow Jones Industrial Average ETF, tracking the Dow Jones Industrial Average) and ITOT (iShares Core S&P Total US Stock Market ETF, tracking the S&P Total Market) overlap by roughly 38% by weight. 7 of DIA's top 10 holdings also appear in ITOT. A 50/50 blend of the two behaves like about 46 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 16 holdings appear in both DIA and ITOT. The weight columns show how much of each fund each name represents.
| Holding | in DIA | in ITOT |
|---|---|---|
| MSFT Microsoft Corporation | 4.20% | 3.79% |
| AAPL Apple Inc. | 3.21% | 5.81% |
| GOOGL Alphabet Inc. | 4.03% | 2.86% |
| AMZN Amazon.com, Inc. | 2.73% | 3.19% |
| NVDA NVIDIA Corporation | 2.22% | 6.63% |
| JPM JPMorgan Chase & Co. | 3.75% | 1.20% |
| JNJ Johnson & Johnson | 2.94% | 0.84% |
| V Visa Inc. | 3.89% | 0.78% |
| CAT Caterpillar Inc. | 11.76% | 0.67% |
| UNH UnitedHealth Group Incorporated | 4.78% | 0.52% |
| HD The Home Depot, Inc. | 3.99% | 0.48% |
| PG The Procter & Gamble Company | 1.69% | 0.47% |
| MRK Merck & Co., Inc. | 1.47% | 0.43% |
| CVX Chevron Corporation | 1.92% | 0.42% |
| GS The Goldman Sachs Group, Inc. | 11.61% | 0.41% |
+ 1 more shared holdings.
Only in DIA
SPDR Dow Jones Industrial Average ETF — US blue-chip (Dow 30). Its biggest holdings that ITOT doesn’t have:
| AMGN Amgen Inc. | 4.10% |
| SHW The Sherwin-Williams Company | 3.92% |
| AXP American Express Company | 3.88% |
| TRV The Travelers Companies, Inc. | 3.78% |
| MCD McDonald's Corporation | 3.04% |
| HON Honeywell International Inc. | 2.59% |
| BA The Boeing Company | 2.44% |
| MMM 3M Company | 1.85% |
Only in ITOT
iShares Core S&P Total US Stock Market ETF — total US market. Its biggest holdings that DIA doesn’t have:
| AVGO BROADCOM INC | 2.45% |
| GOOG ALPHABET INC CLASS C | 2.29% |
| MU MICRON TECHNOLOGY INC | 1.78% |
| META META PLATFORMS INC CLASS A | 1.69% |
| TSLA TESLA INC | 1.62% |
| LLY ELI LILLY | 1.30% |
| AMD ADVANCED MICRO DEVICES INC | 1.30% |
| BRKB BERKSHIRE HATHAWAY INC CLASS B | 1.25% |
So — partly overlapping. Should you hold both?
DIA and ITOT 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 ~46 effective positions (grade B).
Holdings as of — DIA: Jun 29, 2026 (State Street Global Advisors); ITOT: 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 →DIA vs ITOT — FAQ
- How much do DIA and ITOT overlap?
- DIA and ITOT overlap by approximately 38% measured by portfolio weight — that is the share of the smaller fund's holdings (by weight) that also sit inside the other. 7 of DIA's 10 largest holdings are also held by ITOT. They share 16 of their listed top holdings in total.
- Is it redundant to hold both DIA and ITOT?
- 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 (MSFT) while each fund still adds distinct exposure. A 50/50 blend has an effective 46 positions and a B diversification grade.
- What does ITOT hold that DIA doesn't?
- ITOT's largest holdings that DIA doesn't hold include AVGO, GOOG, MU, META, TSLA. Its category is total US market, versus DIA's US blue-chip (Dow 30).
- Which is more concentrated, DIA or ITOT?
- DIA's top 10 holdings are 59% of its listed weight; ITOT's are 58%. The more concentrated fund leans harder on its largest names.