ETF and Mutual Fund Analysis

Holdings as of March 31, 2026

ETF and Mutual Fund Analysis

Overlap, Comparison, and Diversification for Your Portfolio

Home > Compare > IWF vs VIIIX Holdings as of March 31, 2026

IWF vs VIIIX: Portfolio Overlap

iShares Russell 1000 Growth ETF vs Vanguard Institutional Index Fund

57.8%
Weighted portfolio overlap
High Overlap

The two funds are running highly redundant strategies — the same market exposure is paid for through two expense ratios.

IWF
387 equity holdings
as of March 31, 2026
VIIIX
503 equity holdings
as of March 31, 2026
189 stocks held in common
Overlap View Venn Diagram
57.8% OVERLAP IWF VIIIX
Overlapping Holdings
10 Top 10 of 189 shared, by overlap contribution
# Stock IWF VIIIX Overlap%
1
NVDA
 12.95% 7.60% 7.60%
2
AAPL
 11.66% 6.68% 6.68%
3
MSFT
 8.84% 4.93% 4.93%
4
AMZN
 4.67% 3.65% 3.65%
5
GOOGL
 3.54% 3.00% 3.00%
6
AVGO
 4.80% 2.63% 2.63%
7
GOOG
 2.88% 2.40% 2.40%
8
META
 3.46% 2.24% 2.24%
9
TSLA
 3.55% 1.87% 1.87%
10
LLY
 2.66% 1.31% 1.31%
Most Divergent Holdings Stocks held by one fund but absent from the other
Only in IWF — iShares Russell 1000 Growth ETF
StockWeight
SPOT0.27%
NET0.23%
SNOW0.18%
NU0.17%
ALNY0.15%
Only in VIIIX — VANGUARD INSTITUTIONAL INDEX FUND
StockWeight
BRK.B1.57%
JPM1.34%
XOM1.27%
JNJ1.06%
CVX0.70%

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Frequently Asked Questions (FAQs)
What is the portfolio overlap between IWF and VIIIX?

IWF (iShares Russell 1000 Growth ETF) and VIIIX (Vanguard Institutional Index Fund) share 57.8% portfolio overlap as of their March 31, 2026 filings, across 189 common stocks. Overlap is the sum of the smaller weight of each shared stock, so it reads as the share of a dollar that lands on the same companies in both funds.

Do IWF and VIIIX invest in the same stocks?

Largely yes. A substantial portion of both portfolios consists of the same stocks, leaving limited room for differentiation.

What are the top stocks held by both IWF and VIIIX?

The most prominent shared holdings (by combined weight) are: NVDA, AAPL, MSFT. See the full common-holdings table on this page for weights in each fund.

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