FSKAX vs XLB: 1% overlap
Fidelity Total Market Index and Materials Select Sector SPDR Fund share 1.4% of their portfolios by weight — computed as Σ min(wA, wB) over every holding both funds own.
Different holding dates. These holdings were published about 5 months apart — FSKAX as of 2026-02-28, the rest through 2026-07-23. Each fund is compared using its most recent file, so any trading in between shows up as a difference.
You would hold two tickers and get the diversification of 2.0. Two funds that shared nothing would score 2.0; two identical funds score 1.0.
Top shared holdings
FSKAX and XLB hold 21 of the same securities. The ten contributing most to the overlap figure:
| Holding | in FSKAX | in XLB | Δ |
|---|---|---|---|
| NEM | 0.2% | 6.0% | 5.8% |
| FCX | 0.1% | 5.4% | 5.3% |
| SHW | 0.1% | 4.5% | 4.4% |
| ECL | 0.1% | 4.5% | 4.4% |
| CASH | 0.7% | 0.1% | 0.6% |
| APD | 0.1% | 4.7% | 4.6% |
| CTVA | 0.1% | 5.3% | 5.2% |
| VMC | 0.1% | 4.4% | 4.4% |
| MLM | 0.1% | 4.4% | 4.3% |
| NUE | 0.1% | 4.2% | 4.2% |
Where FSKAX and XLB differ
Sector weights as a share of each fund, ordered by the size of the gap rather than the size of the sector — two funds that overlap heavily still usually diverge somewhere.
| Sector | FSKAX | XLB | Δ |
|---|---|---|---|
| Materials | 1.8% | 99.8% | −98.1pp |
| Information Technology | 29.9% | 0.0% | +29.9pp |
| Financials | 12.2% | 0.0% | +12.2pp |
| Health Care | 9.8% | 0.0% | +9.8pp |
| Communication Services | 9.7% | 0.0% | +9.7pp |
| Industrials | 9.6% | 0.0% | +9.6pp |
| Consumer Discretionary | 9.6% | 0.0% | +9.6pp |
| Consumer Staples | 5.1% | 0.0% | +5.1pp |
Δ is FSKAX minus XLB, in percentage points. Sector data is not published by every issuer, so “Unclassified” is a real category rather than a gap in the table.
What each fund holds alone
98.6% of FSKAX by weight, held in no part of XLB.
28.7% of XLB by weight, held in no part of FSKAX.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| FSKAX | XLB | |
|---|---|---|
| Top 10 holdings | 32.1% | 57.4% |
| Positions held | 3,754 | 28 |
| Cost per $10,000 held, per year | $1 | $8 |
Cost is the expense ratio applied to $10,000; it excludes any brokerage commission, bid-ask spread or tax consequence. Figures are facts about the funds, not a suggestion about which to hold.
Frequently asked
How much do FSKAX and XLB overlap?
FSKAX and XLB overlap 1.4% by portfolio weight — largely distinct portfolios. They share 21 holdings. The figure comes from current issuer holdings files (FSKAX as of 2026-02-28, XLB as of 2026-07-23).
How is the overlap between FSKAX and XLB calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If FSKAX holds a stock at 6% and XLB holds the same stock at 4%, 4% counts as shared. The result is bounded between 0% and 100%, and it is computed after looking through any fund-of-funds to the underlying holdings.
Is it redundant to hold both FSKAX and XLB?
That depends on your goals — we state facts, not advice. At 1.4% overlap, each fund still contributes meaningfully distinct exposure.
What does FSKAX own that XLB doesn't?
FSKAX holds 3,754 positions and XLB holds 28; 3,732 of FSKAX's positions don't appear in XLB at all, and they are 98.6% of FSKAX by weight.
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Related comparisons
Sources: issuer holdings files, FSKAX as of 2026-02-28, XLB as of 2026-07-23. Weights are fractions of each fund. Diagnostics, not advice.