Fidelity Mid Cap Growth Index Fund
U.S. stock index fund · tracks Russell Midcap Growth Index
As of its 2026 Q2 report, Fidelity Mid Cap Growth Index Fund held 271 positions with $3.93B in net assets. Its ten largest holdings made up 19.8% of the fund. The FMDGX share class costs 0.05% a year. Over the 12 months to May 2026, FMDGX returned 7.9%, with dividends reinvested. In 2026 Q2 it added 92 new positions and exited 100.
Fidelity Mid Cap Growth Index Fund seeks to provide investment results that correspond to the total return of stocks of mid-capitalization U.S. companies.
The fund tracks the Russell Midcap Growth Index using statistical sampling techniques, holding a representative portfolio of mid-cap U.S. stocks selected for higher growth and valuation characteristics. Because the fund samples rather than holds all index constituents, its returns may diverge from the index. Effective March 24, 2025, the index applies concentration limits capping any single holding at 22.5% and restricting the largest constituents to 45% combined weight.
What you own
| Company | Weight | Value | Shares | Reported price |
|---|---|---|---|---|
DDOGDATADOG INC | 2.33% | $91.52M | 351.5K | $260.36 |
SNOWSNOWFLAKE INC | 2.32% | $91.22M | 358.4K | $254.50 |
2.11% | $82.96M | 338.2K | $245.28 | |
TERTERADYNE INC | 2.06% | $81.10M | 167.6K | $483.84 |
ALABASTERA LABS INC | 2.02% | $79.14M | 163.8K | $483.02 |
1.95% | $76.48M | 341.9K | $223.65 | |
1.88% | $73.94M | 37.3K | $1,981.95 | |
Fidelity Revere Street Trust | 1.75% | $68.53M | — | — |
1.74% | $68.27M | 680.8K | $100.28 | |
1.66% | $65.25M | 76.0K | $858.06 |
Reported price is the fund's own reported value divided by its own reported shares at 2026-06-30 — not a live quote, and not what the fund paid.
The 200 largest of 271 holdings, with the share counts as filed, open with a free account.
What the fund is made of
Percentages are of fund net assets. Rounding, liabilities and short positions can make totals differ from 100%.
| Stocks | 99.45% |
| Cash & short-term | 2.13% |
| Bonds | 0.01% |
| Derivatives | 0.01% |
Derivatives are shown at market value, not notional exposure.
By sector
- Information Technology
- 29.6%
- Industrials
- 20.2%
- Health Care
- 12.1%
- Consumer Discretionary
- 10.6%
- 11 other sectors
- 27.6%
- Information Technology
- 29.6%
- Industrials
- 20.2%
- Health Care
- 12.1%
- Consumer Discretionary
- 10.6%
- Communication Services
- 5.5%
- Financials
- 4.5%
- International
- 4.5%
- Energy
- 3.8%
- Utilities
- 2.6%
- Real Estate
- 2.1%
- Cash
- 2.1%
- Consumer Staples
- 1.9%
- Materials
- 0.5%
- Government
- 0.0%
- Other
- 0.0%
How it has done
FMDGX share class · total returns with dividends reinvested
Volatility over the last 12 months: 11.92%. Past returns are a record, not a forecast.
Jun 2026 has been filed since the trailing figures were struck, so it is not in the table above or the curve — every figure here shares one cut-off, which is what makes them comparable with other funds.
Fees & fund details
Fidelity Mid Cap Growth Index Fund is a U.S. equity index fund that tracks the Russell Midcap Growth Index. 42% of FMDGX’s stock holdings are in companies whose revenue grew in the top quartile of U.S. companies over the last five fiscal years (covering 90% of the fund’s equity).
- Asset class
- Equity
- Region
- United States
- Management
- Index (passive)
- Fund type
- Open-end fund
- Expense ratio, by class
- 0.05%· FMDGX 0.05%
- Portfolio turnover
- 53.00% a year · as of 2025 Q3
Turnover is how much of the portfolio was replaced in a year.
Classified from what the fund holds, not from its name · 2026 Q2. The summary is a paraphrase of the prospectus; the objective is verbatim.
What changed this quarter
Positions that entered or left the fund since its previous filing. Positions that were only resized are not listed.
92 new· the largest 8
100 exited· the largest 8
Debt profile
What this fund holds — value-weighted across its bond and securitized long positions · as of 2026-06-30
Share of the fund's debt by how its coupon behaves — the fact that decides whether a rate move reaches this portfolio at all.
| Fixed rate | 100.0% |
Share of the fund's debt value in each maturity band, shortest first.
| <1y | 100.0% |
Based on what filers reported; a filer that never reported a flag also reads as none.
Understand how this fund fits with the rest.
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