FNSOX vs. BIL

Last updated Jun 5, 2026

FNSOX (Fidelity Short-Term Bond Index Fund) and BIL (SPDR Bloomberg 1-3 Month T-Bill ETF) are both funds - FNSOX is a Total Bond Market fund managed by Fidelity, while BIL is a Government Bonds fund tracking the Bloomberg 1-3 Month U.S. Treasury Bill Index. Over the past 5 years, FNSOX returned 1.58%/yr vs 3.41%/yr for BIL. At a 0.04 correlation, their price movements are largely independent. FNSOX charges 0.03%/yr vs 0.14%/yr for BIL.

Performance

FNSOX vs. BIL - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Short-Term Bond Index Fund (FNSOX) and SPDR Bloomberg 1-3 Month T-Bill ETF (BIL). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, FNSOX achieves a 0.27% return, which is significantly lower than BIL's 1.49% return.

FNSOX

• 1D: -0.10%
• 1M: -0.03%
• YTD: 0.27%
• 6M: 0.62%
• 1Y: 3.46%
• 3Y*: 4.44%
• 5Y*: 1.58%
• 10Y*: —

BIL

• 1D: 0.00%
• 1M: 0.27%
• YTD: 1.49%
• 6M: 1.76%
• 1Y: 3.87%
• 3Y*: 4.64%
• 5Y*: 3.41%
• 10Y*: 2.18%

*Multi-year figures are annualized to reflect compound growth (CAGR)

FNSOX vs. BIL - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
FNSOX Fidelity Short-Term Bond Index Fund	0.27%	6.01%	3.90%	4.90%	-5.76%	-1.25%	4.28%	4.95%	1.14%	-0.22%
BIL SPDR Bloomberg 1-3 Month T-Bill ETF	1.49%	4.15%	5.19%	4.94%	1.40%	-0.10%	0.40%	2.03%	1.74%	0.13%

Correlation

The correlation between FNSOX and BIL is -0.09, meaning there is essentially no relationship between their price movements. Each responds to its own set of market drivers, making them strong candidates for combining in a diversified portfolio.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	-0.09
Correlation (3Y) Calculated over the trailing 3-year period	0.02
Correlation (5Y) Calculated over the trailing 5-year period	0.07
Correlation (All Time) Calculated using the full available price history since Nov 1, 2017	0.04

The correlation between FNSOX and BIL shifts across timeframes, from -0.09 (1 year) to 0.07 (5 years), reflecting how their relationship changes across market environments.

Return for Risk

FNSOX vs. BIL — Risk / Return Rank

Compare risk-adjusted metric ranks to identify better-performing investments over the past 12 months.

FNSOX

FNSOX Risk / Return Rank: 42
FNSOX Sharpe Ratio Rank: 38
FNSOX Sortino Ratio Rank: 47
FNSOX Omega Ratio Rank: 44
FNSOX Calmar Ratio Rank: 43
FNSOX Martin Ratio Rank: 38

BIL

BIL Risk / Return Rank: 100
BIL Sharpe Ratio Rank: 100
BIL Sortino Ratio Rank: 100
BIL Omega Ratio Rank: 100
BIL Calmar Ratio Rank: 100
BIL Martin Ratio Rank: 100

The rank (0–100) shows how this investment's returns compare to the risk taken. Higher = better. Based on the past 12 months of data, combining Sharpe, Sortino, and other metrics used by quantitative funds and institutional investors.

FNSOX vs. BIL - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Short-Term Bond Index Fund (FNSOX) and SPDR Bloomberg 1-3 Month T-Bill ETF (BIL). Risk-adjusted metrics are performance indicators that assess an investment's returns in relation to its risk, enabling a more accurate comparison of different investment options.

	FNSOX	BIL	Difference
Sharpe ratio: Return per unit of total volatility	1.78	19.71	-17.93
Sortino ratio: Return per unit of downside risk	2.90	174.16	-171.26
Omega ratio: Gain probability vs. loss probability	1.36	87.91	-86.55
Calmar ratio: Return relative to maximum drawdown	2.50	355.35	-352.86
Martin ratio: Return relative to average drawdown	8.25	2,817.77	-2,809.52
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

FNSOX vs. BIL - Sharpe Ratio Comparison

The current FNSOX Sharpe Ratio is 1.78, which is lower than the BIL Sharpe Ratio of 19.71. The chart below compares the historical Sharpe Ratios of FNSOX and BIL, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Sharpe Ratios by Period

	FNSOX	BIL	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.78	19.71	-17.93
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.55	13.15	-12.60
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	8.51	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.83	2.78	-1.94

Drawdowns

FNSOX vs. BIL - Drawdown Comparison

The maximum FNSOX drawdown since its inception was -8.92%, which is greater than BIL's maximum drawdown of -0.78%. Use the drawdown chart below to compare losses from any high point for FNSOX and BIL.

Drawdown Indicators

	FNSOX	BIL	Difference
Max Drawdown Largest peak-to-trough decline	-8.92%	-0.78%	-8.14%
Max Drawdown (1Y) Largest decline over 1 year	-1.47%	-0.01%	-1.46%
Max Drawdown (3Y) Largest decline over 3 years	-1.51%	-0.01%	-1.50%
Max Drawdown (5Y) Largest decline over 5 years	-8.77%	-0.10%	-8.67%
Max Drawdown (10Y) Largest decline over 10 years	—	-0.21%	—
Current Drawdown Current decline from peak	-0.70%	0.00%	-0.70%
Average Drawdown Average peak-to-trough decline	-1.73%	-0.26%	-1.47%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.45%	0.00%	+0.45%

Volatility

FNSOX vs. BIL - Volatility Comparison

Fidelity Short-Term Bond Index Fund (FNSOX) has a higher volatility of 0.65% compared to SPDR Bloomberg 1-3 Month T-Bill ETF (BIL) at 0.06%. This indicates that FNSOX's price experiences larger fluctuations and is considered to be riskier than BIL based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FNSOX	BIL	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.65%	0.06%	+0.59%
Volatility (6M) Calculated over the trailing 6-month period	1.51%	0.13%	+1.38%
Volatility (1Y) Calculated over the trailing 1-year period	2.07%	0.20%	+1.87%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	2.89%	0.26%	+2.63%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	2.47%	0.26%	+2.21%

FNSOX vs. BIL - Expense Ratio Comparison

FNSOX has a 0.03% expense ratio, which is lower than BIL's 0.14% expense ratio. Despite the difference, both funds are considered low-cost compared to the broader market, where average expense ratios usually range from 0.3% to 0.9%.

Dividends

FNSOX vs. BIL - Dividend Comparison

FNSOX's dividend yield for the trailing twelve months is around 3.53%, less than BIL's 3.86% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016
BIL SPDR Bloomberg 1-3 Month T-Bill ETF	3.86%	4.13%	5.03%	4.92%	1.35%	0.00%	0.30%	2.05%	1.66%	0.68%	0.07%
FNSOX Fidelity Short-Term Bond Index Fund	3.53%	3.22%	2.80%	1.74%	0.81%	0.80%	1.54%	2.61%	2.04%	0.34%	0.00%

Frequently Asked Questions

Can I hold both FNSOX and BIL in my portfolio?

FNSOX and BIL have a correlation of -0.09, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, FNSOX or BIL?

FNSOX has higher volatility (0.65%) compared to BIL (0.06%). In terms of maximum drawdown, FNSOX dropped -8.92% vs BIL's -0.78%.

Which has better risk-adjusted returns?

BIL currently has the higher Sharpe Ratio (19.71 vs 1.78), meaning it's delivered slightly more return per unit of risk over the trailing 12 months. However, this ranking shifts over time - use the Risk/Return Score above for a more comprehensive view that combines Sharpe, Sortino, and other measures used by quantitative funds.