ANCFX vs MUB: 0% overlap
American Funds Fundamental Investors A and iShares National Muni Bond ETF share 0.0% 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 4 months apart — ANCFX as of 2026-03-31, 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
ANCFX and MUB hold 0 of the same securities. The ten contributing most to the overlap figure:
| Holding | in ANCFX | in MUB | Δ |
|---|
Where ANCFX and MUB 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 | ANCFX | MUB | Δ |
|---|---|---|---|
| State Tax-Backed | 0.0% | 30.7% | −30.7pp |
| Information Technology | 27.8% | 0.0% | +27.8pp |
| Local Tax-Backed | 0.0% | 14.9% | −14.9pp |
| Utilities | 2.1% | 16.8% | −14.7pp |
| Industrials | 12.0% | 0.0% | +12.0pp |
| School Districts | 0.0% | 10.2% | −10.2pp |
| Transportation | 0.0% | 10.2% | −10.2pp |
| Consumer Staples | 9.4% | 0.0% | +9.4pp |
Δ is ANCFX minus MUB, 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
99.1% of ANCFX by weight, held in no part of MUB.
101.0% of MUB by weight, held in no part of ANCFX.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| ANCFX | MUB | |
|---|---|---|
| Top 10 holdings | 34.1% | 17.2% |
| Positions held | 233 | 969 |
| Cost per $10,000 held, per year | $61 | $5 |
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 ANCFX and MUB overlap?
ANCFX and MUB overlap 0.0% by portfolio weight — largely distinct portfolios. They share 0 holdings. The figure comes from current issuer holdings files (ANCFX as of 2026-03-31, MUB as of 2026-07-23).
How is the overlap between ANCFX and MUB calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If ANCFX holds a stock at 6% and MUB 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 ANCFX and MUB?
That depends on your goals — we state facts, not advice. At 0.0% overlap, each fund still contributes meaningfully distinct exposure.
What does ANCFX own that MUB doesn't?
ANCFX holds 233 positions and MUB holds 969; 232 of ANCFX's positions don't appear in MUB at all, and they are 99.1% of ANCFX by weight.
You probably hold more than two funds
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Related comparisons
Sources: issuer holdings files, ANCFX as of 2026-03-31, MUB as of 2026-07-23. Weights are fractions of each fund. Diagnostics, not advice.