IDU vs VOO: Holdings Overlap
iShares · 44 holdings · $1.5B · as of 2026-04-30
Vanguard · 504 holdings · $1.03T · as of 2026-03-31
Holdings snapshots are 30 days apart (IDU: 2026-04-30, VOO: 2026-03-31). Weights and index membership change between snapshots, so the true current overlap is typically higher than shown. For funds tracking the same index, the gap can be 5–15 points.
How similar are IDU and VOO?
iShares U.S. Utilities ETF (IDU, by iShares) holds 44 positions; Vanguard 500 Index Fund (VOO, by Vanguard) holds 504. They have 33 holdings in common, and by portfolio weight the two funds are 2.8% identical. In practical terms the pair is essentially distinct, holding almost none of the same securities.
- Overlap by Weight
- 2.8%Sum of the smaller weight of each shared holding
- Shared Holdings
- 33IDU holds 44 · VOO holds 504
- Weight in Shared Holdings
- IDU 94%·VOO 3%Share of each fund's weight in stocks both funds own
Based on each fund's latest official holdings. How is this calculated?
What makes each fund different
Only in IDU
11 of 44 positions (5.5% of the fund) are not held by VOO.
Sector Breakdown
| Sector | IDU | VOO |
|---|---|---|
| Utilities | 91.2% | 2.5% |
| Information Technology | 0.0% | 32.7% |
| Financials | 0.0% | 12.4% |
| Communication Services | 0.0% | 10.5% |
| Consumer Discretionary | 0.0% | 9.9% |
| Other Sectors | 8.6% | 31.8% |
Share of each fund's portfolio weight by GICS-style sector, compiled from issuer fund data and our own classification of the holdings, not the issuers' published sector charts.
Performance
| Fund | 1M | YTD | 1Y | 3Y (ann.) | 5Y (ann.) | 10Y (ann.) | Yield |
|---|---|---|---|---|---|---|---|
| IDU | -4.3% | +3.5% | +2.8% | +14.4% | +8.5% | +8.6% | 2.27% |
| VOO | +3.4% | +14.0% | +23.7% | +21.3% | +13.4% | +15.4% | 1.03% |
Total returns including dividends, from adjusted daily closes as of 2026-08-07. 3Y/5Y/10Y are annualized. Yield is trailing-12-month distributions over the last close. Past performance does not predict future results.
Project the growth of $10,000 in IDU vs VOO →
Shared Holdings(33)
The top 10 shared positions account for 56% of the overlap, led by NEE, SO and DUK.
 NEENextEra Energy Inc COM | 12.22% | 0.35% | 0.35% |
|---|---|---|---|
 SOSouthern Co. (The) | 6.38% | 0.19% | 0.19% |
 DUKDuke Energy Corp COM NEW | 6.03% | 0.18% | 0.18% |
 CEGConstellation Energy Corp. COM | 5.84% | 0.16% | 0.16% |
 WMWaste Management, Inc. COM | 5.15% | 0.15% | 0.15% |
 AEPAmerican Electric Power Co, Inc. COM | 4.39% | 0.13% | 0.13% |
 SRESempra COM | 3.71% | 0.11% | 0.11% |
 DDominion Energy Inc COM | 3.29% | 0.09% | 0.09% |
 ETREntergy Corporation COM | 3.15% | 0.09% | 0.09% |
 EXCExelon Corp. COM | 2.78% | 0.09% | 0.09% |
 VSTVistra Corp. COMMON STOCK | 3.20% | 0.09% | 0.09% |
 XELXcel Energy Inc COM | 2.94% | 0.08% | 0.08% |
 RSGRepublic Services, Inc., Class A | 2.54% | 0.08% | 0.08% |
 EDConsolidated Edison, Inc. COM | 2.40% | 0.07% | 0.07% |
 PEGPublic Service Enterprise Group Incorporated COM | 2.44% | 0.07% | 0.07% |
 PCGPG&E Corporation COM | 2.18% | 0.07% | 0.07% |
 WECWEC Energy Group Inc. COM | 2.30% | 0.07% | 0.07% |
 NRGNRG Energy, Inc. COM NEW | 1.91% | 0.06% | 0.06% |
 ATOAtmos Energy Corp. COM | 1.82% | 0.05% | 0.05% |
 AEEAmeren Corp. COM | 1.84% | 0.05% | 0.05% |
 DTEDTE Energy Co. COM | 1.88% | 0.05% | 0.05% |
 PPLPPL Corporation COM | 1.66% | 0.05% | 0.05% |
 CNPCenterpoint Energy Inc COM | 1.70% | 0.05% | 0.05% |
 EIXEdison International COM | 1.59% | 0.05% | 0.05% |
 AWKAmerican Water Works Company, Inc. COM | 1.50% | 0.05% | 0.05% |
Frequently Asked Questions
How much do IDU and VOO overlap?
IDU and VOO overlap by 2.8% of portfolio weight. They share 33 holdings (IDU holds 44 positions and VOO holds 504), based on each fund's latest SEC-reported holdings.
Is it redundant to own both IDU and VOO?
The two portfolios are 2.8% identical by weight. Owning both is genuine diversification: the funds hold almost none of the same securities.
What are the biggest shared holdings of IDU and VOO?
The largest positions held by both funds are NEE, SO, DUK, CEG and WM. Together the top 10 shared positions account for 56% of the total overlap.
What does IDU own that VOO doesn't?
11 positions (5.5% of IDU) are unique to IDU, led by TLN, CLH and WTRG. In the other direction, 471 positions (97.0% of VOO) are unique to VOO.