VBIL

ETF performance based on market prices. Drag on chart to select period. Sharpe Ratio uses the one-month T-bill as the risk-free rate. From 10/7/2025 to 10/7/2026.

ETF performance based on market prices. Returns for periods greater than one year are annualized. As of 10/7/2026.

* partial year — the series ran for only part of it (its first year, or the year it closed); the figure is the return over the part it did run. ETF performance based on market prices. As of 10/7/2026.

Family

Vanguard

Registrant

VANGUARD INSTITUTIONAL INDEX FUNDS

Type

ETF

Asset Class

Fixed Income

Peer Asset Class

Cash

Region

US

Peer Group Benchmark

BIL (0.55)

Prospectus Benchmark

Bloomberg U.S. Aggregate Float Adjusted Index

Peer Group

Cash & Ultra-Short (157 peers)

1Y Peer Percentile

62

Expense Ratio

0.06%

AUM

$12.7B

Yield

3.53%

Inception

2/12/2025

Holdings (Reported)

27

Turnover

0%

Equity

0%

Derivatives

0%

Net Equity Exposure

0%

The fund invests at least 80% of its assets in bonds that comprise the Bloomberg U.S. Treasury Bills 0-3 Months Index, which includes U.S. Treasury bonds with maturities of 3 months or less. It employs a sampling strategy to approximate the full index in terms of key risk factors and characteristics, while maintaining a dollar-weighted average maturity consistent with the index, expected to be under 3 months. As of December 31, 2025, the dollar-weighted average maturity of the Target Index was 1 month.

Expense ratio and its components from the fund's prospectus fee table. Turnover from the SEC annual report (2/27/2026). Yield as of 10/6/2026, AUM 9/30/2026. Holdings, asset class, style, peer group and exposures as of 6/30/2026. Strategy summary from the fund's prospectus.

Hover or click for factor definitions. Weighted average of underlying company-level values with weights equal to position size. Solid blue dots mark the fund's position within the clean equity fund universe (5th–95th percentile scale); the shaded band spans the fund's broad class (Cash Funds) 25th–75th percentile, notched at the median. Holdings as of 6/30/2026. Stock-level data as of 8/31/2026. Expense ratio, yield, and turnover as of 10/6/2026. AUM as of 9/30/2026.

Shares are percentages of the holdings that carry a country, not portfolio weights. Based on N-PORT domicile; ADRs list under their exchange. Holdings as of 6/30/2026. Stock-level data as of 8/31/2026.

27 positions (top 10 shown, create free account for full holdings)

Sector, country and factor detail need a security match; the share of weight that matched is a member figure, so the rows without one appear here with those columns blank. Holdings as of 6/30/2026. Stock-level data as of 8/31/2026.

Hover or click for definitions. Solid blue dots mark the fund: percentage rows on a 0–100% scale, holdings counts log-scaled across the clean-universe 5th–95th percentile range. The shaded band spans the fund's broad class (Cash Funds) 25th–75th percentile, notched at the median. Holdings as of 6/30/2026.

One sub-card per benchmark: the market primary, then the style secondary — the gap between them is the style sleeve itself. Both anchors are Sparkline-inferred (market from asset class and region, style from the holdings size-and-style map), not the fund's official prospectus benchmark. Solid blue dot marks the fund; the shaded band spans the reference set's 25th–75th percentile, notched at the median (band follows the Peer Universe selector). Active Share compares the fund's book with the benchmark's, share for share; Tracking Error is the annualized daily deviation over the trailing two years (ruler runs to just past the universe's 95th percentile, or past the fund's own figure where that is larger); Benchmark Correlation is the plain daily correlation over the trailing year. Hover the labels for full definitions.

Sparkline's own holdings-based peer taxonomy (252 share classes across 157 funds). One share class shown per fund — the exchange-listed class where the SEC series has one, else its longest-history class; percentile ranks and medians are computed against the same deduped set. Quartile chips fill the layer the fund's rank falls in (top layer = best quartile). Funds without a full return history rank only on the horizons they cover.

Nearest funds across the whole universe, by holdings and behavior — the peer taxonomy is ignored, so matches can come from any category.

The method columns are members-only — create a free account to see these figures.

Rows are the consensus top matches (a fund must place in at least two methods' top 250 to qualify, and matches missing more than one of this fund's own methods are not ranked — a row scored on fewer methods is a noisier estimate, not a better match). Click a method column to see that method's own top matches across the whole universe instead. Gray (N) beside each method's metric is that fund's rank in the whole universe on that method. Similarity is a percentile among match-grade fund pairs, 0–100 — 87 means the pair is closer than 87% of the strongest matches in the universe, averaged across the methods — so it compares across funds: index clones tie at the top with thousands of other clone pairs, so scores top out in the high 80s to 90s, while a one-of-a-kind fund's best match can score in the 30s. Rows are ordered by the Consensus Rank — the geometric mean of those universe ranks, shown in each cell's tooltip — and the score is held down the list to the level of the closest match above it, so equal scores mean equally close and the number reads as a floor. A dash means that method has no figure for the pair at all (one of them lacks the holdings or return history it needs). Hover a column header for each method's definition. The “Top…” strips above compare against every fund's own top match across the whole universe (they deliberately don't follow the Peer Universe selector); Top Similarity is simply the best match's score, with no reference band; the Holdings and Active Tilt strips carry no reference band because computing every fund's best book overlap would require a full holdings scan per fund — the dot stands alone on its natural 0–100% scale. One share class shown per fund, and a fund's own sister share classes are excluded from its Top-match strips. Holdings as of 6/30/2026. Consensus Rank is the geometric mean of the match's universe-wide rank across the methods (#1.0 = top match on every one). Holdings Overlap = common-holdings weight (sum of the minimum weight across shared positions, long only). Active Tilt Overlap = the same statistic on active weights (holdings minus the fund's own default benchmark, floored at 0), which strips the benchmark ballast that dominates raw overlap. Return Correlation = correlation of market-hedged daily returns over the trailing two years (CAPM residuals), so only market-beta co-movement is removed; requires ~18 months of daily history (378 of the window's 504 trading days).