IJR vs TRRBX: 0% overlap
iShares Core S&P Small-Cap ETF and T. Rowe Price Retirement 2020 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 5 months apart — TRRBX 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
IJR and TRRBX hold 0 of the same securities. The ten contributing most to the overlap figure:
| Holding | in IJR | in TRRBX | Δ |
|---|
Where IJR and TRRBX 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 | IJR | TRRBX | Δ |
|---|---|---|---|
| Unclassified | 0.0% | 99.9% | −99.9pp |
| Industrials | 18.5% | 0.0% | +18.5pp |
| Financials | 17.8% | 0.0% | +17.8pp |
| Consumer Discretionary | 13.8% | 0.0% | +13.8pp |
| Information Technology | 12.1% | 0.0% | +12.1pp |
| Health Care | 10.5% | 0.0% | +10.5pp |
| Real Estate | 6.2% | 0.0% | +6.2pp |
| Energy | 5.3% | 0.0% | +5.3pp |
Δ is IJR minus TRRBX, 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
99.9% of IJR by weight, held in no part of TRRBX.
99.9% of TRRBX by weight, held in no part of IJR.
A large count with a small weight is the usual shape: the positions one fund adds are typically its smallest ones.
Concentration and cost
| IJR | TRRBX | |
|---|---|---|
| Top 10 holdings | 6.6% | 69.2% |
| Positions held | 603 | 31 |
| Cost per $10,000 held, per year | $6 | $53 |
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 IJR and TRRBX overlap?
IJR and TRRBX overlap 0.0% by portfolio weight — largely distinct portfolios. They share 0 holdings. The figure comes from current issuer holdings files (IJR as of 2026-07-23, TRRBX as of 2026-02-28).
How is the overlap between IJR and TRRBX calculated?
As the sum of the smaller weight in each fund, over every holding both funds own: Σ min(wA, wB). If IJR holds a stock at 6% and TRRBX 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 IJR and TRRBX?
That depends on your goals — we state facts, not advice. At 0.0% overlap, each fund still contributes meaningfully distinct exposure.
What does IJR own that TRRBX doesn't?
IJR holds 603 positions and TRRBX holds 31; 602 of IJR's positions don't appear in TRRBX at all, and they are 99.9% of IJR by weight.
You probably hold more than two funds
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Related comparisons
Sources: issuer holdings files, IJR as of 2026-07-23, TRRBX as of 2026-02-28. Weights are fractions of each fund. Diagnostics, not advice.