VBISX Performance — Vanguard Short-Term Bond Index Fund, Investor Shares
Data updated: 2026-08-28
VBISX returned +0.48% year to date and +2.94% over one year to Jun 2026. Annualised returns are +4.54% over 3 years and +1.60% over 5 years. Against its Short-Term Government Bond category average the fund came out behind over three years but ahead over one: $100 invested three years ago grew to $114, against $115 for the category, and to $103 over one year, against $103. Volatility over the past three years was 2.27% a year. In the 12 months to Jun 2026 the fund took in a net $6.4B, and assets reached $69.75B.
VBISX Growth of $100
What $100 invested in Vanguard Short-Term Bond Index Fund grew to, compounded from monthly returns reported on SEC Form N-PORT, against the Short-Term Government Bond category average over the same months.
| Period | VBISX | Category average |
|---|---|---|
| 1 year (Jul 2025 – Jun 2026) | $103 | $103 |
| 3 years (Jul 2023 – Jun 2026) | $114 | $115 |
| 5 years (Jul 2021 – Jun 2026) | $108 | $111 |
| Since data start (Jul 2019 – Jun 2026) | $114 | $118 |
VBISX Trailing Returns
Total returns to Jun 2026, from SEC N-PORT.
| Period | Total return |
|---|---|
| YTD | +0.48% |
| 1 year | +2.94% |
| 3 years (annualised) | +4.54% |
| 5 years (annualised) | +1.60% |
VBISX Annual Returns
Calendar-year total returns of Vanguard Short-Term Bond Index Fund, compounded from monthly SEC N-PORT returns. Partial years show the months covered.
| Year | Total return |
|---|---|
| 2026 (Jan–Jun) | +0.48% |
| 2025 | +5.98% |
| 2024 | +3.64% |
| 2023 | +4.79% |
| 2022 | −5.61% |
| 2021 | −1.15% |
| 2020 | +4.61% |
| 2019 (Jul–Dec) | +1.28% |
VBISX Monthly Returns
Monthly total returns as reported on SEC Form N-PORT.
| Year | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 2026 | +0.1% | +0.8% | −0.8% | +0.2% | 0.0% | +0.1% | — | — | — | — | — | — |
| 2025 | +0.5% | +1.0% | +0.5% | +0.9% | −0.3% | +0.8% | −0.1% | +1.1% | +0.2% | +0.3% | +0.6% | +0.2% |
| 2024 | +0.3% | −0.7% | +0.4% | −0.7% | +1.0% | +0.7% | +1.5% | +1.0% | +1.0% | −1.1% | +0.4% | −0.1% |
| 2023 | +1.3% | −1.3% | +1.9% | +0.5% | −0.5% | −0.6% | +0.3% | +0.2% | −0.4% | 0.0% | +1.8% | +1.6% |
| 2022 | −1.0% | −0.6% | −1.9% | −1.0% | +0.7% | −0.9% | +1.0% | −1.4% | −1.9% | −0.2% | +1.4% | −0.1% |
| 2021 | 0.0% | −0.4% | −0.3% | +0.3% | +0.2% | −0.2% | +0.4% | −0.1% | −0.3% | −0.5% | −0.1% | −0.2% |
| 2020 | +0.9% | +1.1% | +0.2% | +0.8% | +0.5% | +0.4% | +0.3% | 0.0% | 0.0% | −0.1% | +0.2% | +0.1% |
| 2019 | — | — | — | — | — | — | 0.0% | +1.0% | −0.1% | +0.3% | 0.0% | +0.1% |
VBISX Risk
Risk measures from monthly returns over Jul 2023 – Jun 2026.
- 3-year volatility (annualised): 2.27%
- 3-year Sharpe ratio: 0.02 (vs 4.5% risk-free rate)
- Best month: +1.76% (Nov 2023)
- Worst month: −1.07% (Oct 2024)
VBISX Fund Flows
Monthly money in and out of Vanguard Short-Term Bond Index Fund, from SEC Form N-PORT.
- 12-month net flow: $6.4B
- 12-month gross sales (incl. reinvestments): $17.6B
- Sales ÷ redemptions: 1.57×
| Month | Sales | Redemptions | Net flow |
|---|---|---|---|
| Jun 2026 | $1.5B | $1.9B | −$364.2M |
| May 2026 | $1.2B | $527.9M | $632.6M |
| Apr 2026 | $945.9M | $693.6M | $252.3M |
| Mar 2026 | $1.5B | $890.8M | $627.5M |
| Feb 2026 | $1.5B | $988.2M | $495.6M |
| Jan 2026 | $1.7B | $857.7M | $831.6M |
| Dec 2025 | $1.9B | $1.5B | $409.9M |
| Nov 2025 | $2.8B | $325.6M | $2.4B |
| Oct 2025 | $1.7B | $1.7B | −$5.0M |
| Sep 2025 | $1.0B | $478.3M | $551.8M |
| Aug 2025 | $992.5M | $405.3M | $587.2M |
| Jul 2025 | $919.9M | $951.7M | −$31.7M |
VBISX Assets Under Management
Net assets of Vanguard Short-Term Bond Index Fund by report date, from SEC N-PORT filings.
| Report date | Net assets |
|---|---|
| 2026-06-30 | $69.75B |
| 2026-03-31 | $69.68B |
| 2025-12-31 | $68.19B |
| 2025-09-30 | $65.37B |
| 2025-06-30 | $64.08B |
| 2025-03-31 | $60.12B |
| 2024-12-31 | $58.25B |
| 2024-09-30 | $59.30B |
| 2024-06-30 | $57.70B |
| 2024-03-31 | $57.26B |
| 2023-12-31 | $57.27B |
| 2023-09-30 | $58.62B |
For information only. Not investment advice: figures are as reported in SEC filings and may contain errors or be out of date. Past performance does not guarantee future results.