FNSOX vs. FXNAX

Last updated Jun 24, 2026

FNSOX (Fidelity Short-Term Bond Index Fund) and FXNAX (Fidelity U.S. Bond Index Fund) are both Total Bond Market funds from Fidelity. Over the past 5 years, FNSOX returned 1.59%/yr vs -0.05%/yr for FXNAX. Their correlation of 0.83 suggests significant overlap in exposure. FNSOX charges 0.03%/yr vs 0.03%/yr for FXNAX.

Performance

FNSOX vs. FXNAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Short-Term Bond Index Fund (FNSOX) and Fidelity U.S. Bond Index Fund (FXNAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, FNSOX achieves a 0.07% return, which is significantly lower than FXNAX's 0.11% return.

FNSOX

• 1D: -0.10%
• 1M: 0.17%
• YTD: 0.07%
• 6M: 0.42%
• 1Y: 3.05%
• 3Y*: 4.48%
• 5Y*: 1.59%
• 10Y*: —

FXNAX

• 1D: -0.29%
• 1M: 0.61%
• YTD: 0.11%
• 6M: 0.43%
• 1Y: 4.25%
• 3Y*: 3.88%
• 5Y*: -0.05%
• 10Y*: 1.44%

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

FNSOX vs. FXNAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
FNSOX Fidelity Short-Term Bond Index Fund	0.07%	6.01%	3.90%	4.90%	-5.76%	-1.25%	4.28%	4.95%	1.14%	-0.22%
FXNAX Fidelity U.S. Bond Index Fund	0.11%	7.14%	1.35%	5.82%	-13.55%	-2.10%	7.63%	8.50%	0.04%	0.47%

Correlation

The correlation between FNSOX and FXNAX is 0.86, indicating a strong positive relationship between their price movements. Combining them offers limited diversification - they tend to fall together during downturns.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.86
Correlation (3Y) Calculated over the trailing 3-year period	0.86
Correlation (5Y) Calculated over the trailing 5-year period	0.87
Correlation (All Time) Calculated using the full available price history since Oct 31, 2017	0.83

The correlation between FNSOX and FXNAX has been stable across timeframes, ranging from 0.83 to 0.87 - a consistent structural relationship.

Return for Risk

FNSOX vs. FXNAX — Risk / Return Rank

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

FNSOX

FNSOX Risk / Return Rank: 38
FNSOX Sharpe Ratio Rank: 35
FNSOX Sortino Ratio Rank: 43
FNSOX Omega Ratio Rank: 40
FNSOX Calmar Ratio Rank: 38
FNSOX Martin Ratio Rank: 32

FXNAX

FXNAX Risk / Return Rank: 18
FXNAX Sharpe Ratio Rank: 18
FXNAX Sortino Ratio Rank: 20
FXNAX Omega Ratio Rank: 17
FXNAX Calmar Ratio Rank: 20
FXNAX Martin Ratio Rank: 18

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. FXNAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Short-Term Bond Index Fund (FNSOX) and Fidelity U.S. Bond Index Fund (FXNAX). 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.

Values are calculated on a 1-year rolling basis and updated daily. Risk-adjusted metrics are more stable over longer periods — use the period switch above to explore them.

	FNSOX	FXNAX	Difference
Sharpe ratio: Return per unit of total volatility	1.57	1.14	+0.43
Sortino ratio: Return per unit of downside risk	2.52	1.73	+0.79
Omega ratio: Gain probability vs. loss probability	1.31	1.20	+0.11
Calmar ratio: Return relative to maximum drawdown	2.22	1.52	+0.70
Martin ratio: Return relative to average drawdown	6.88	4.36	+2.52

FNSOX vs. FXNAX - Sharpe Ratio Comparison

The current FNSOX Sharpe Ratio is 1.57, which is higher than the FXNAX Sharpe Ratio of 1.14. The chart below compares the historical Sharpe Ratios of FNSOX and FXNAX, calculated using daily returns over the previous 12 months. A higher Sharpe Ratio indicates better risk-adjusted performance relative to the risk-free rate.

Drawdowns

FNSOX vs. FXNAX - Drawdown Comparison

The maximum FNSOX drawdown since its inception was -8.92%, smaller than the maximum FXNAX drawdown of -19.51%. Use the drawdown chart below to compare losses from any high point for FNSOX and FXNAX.

Drawdown Indicators

	FNSOX	FXNAX	Difference
Max Drawdown Largest peak-to-trough decline	-8.92%	-19.51%	+10.59%
Max Drawdown (1Y) Largest decline over 1 year	-1.47%	-2.94%	+1.47%
Max Drawdown (3Y) Largest decline over 3 years	-1.51%	-6.16%	+4.65%
Max Drawdown (5Y) Largest decline over 5 years	-8.77%	-18.54%	+9.77%
Max Drawdown (10Y) Largest decline over 10 years	—	-19.51%	—
Current Drawdown Current decline from peak	-0.90%	-3.17%	+2.27%
Average Drawdown Average peak-to-trough decline	-1.73%	-3.86%	+2.13%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.47%	1.02%	-0.55%

Volatility

FNSOX vs. FXNAX - Volatility Comparison

The current volatility for Fidelity Short-Term Bond Index Fund (FNSOX) is 0.71%, while Fidelity U.S. Bond Index Fund (FXNAX) has a volatility of 1.16%. This indicates that FNSOX experiences smaller price fluctuations and is considered to be less risky than FXNAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FNSOX	FXNAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.71%	1.16%	-0.45%
Volatility (6M) Calculated over the trailing 6-month period	1.56%	2.90%	-1.34%
Volatility (1Y) Calculated over the trailing 1-year period	2.08%	3.92%	-1.84%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	2.90%	6.08%	-3.18%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	2.47%	5.01%	-2.54%

FNSOX vs. FXNAX - Expense Ratio Comparison

FNSOX has a 0.03% expense ratio, which is higher than FXNAX's 0.03% expense ratio. However, 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. FXNAX - Dividend Comparison

FNSOX's dividend yield for the trailing twelve months is around 3.54%, less than FXNAX's 3.72% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FNSOX Fidelity Short-Term Bond Index Fund	3.54%	3.22%	2.80%	1.74%	0.81%	0.80%	1.54%	2.61%	2.04%	0.34%	0.00%	0.00%
FXNAX Fidelity U.S. Bond Index Fund	3.72%	3.58%	3.40%	3.15%	1.81%	1.74%	2.92%	2.68%	2.74%	2.57%	2.76%	2.52%

Frequently Asked Questions

Can I hold both FNSOX and FXNAX in my portfolio?

FNSOX and FXNAX have a correlation of 0.86, 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 FXNAX?

FXNAX has higher volatility (1.16%) compared to FNSOX (0.71%). In terms of maximum drawdown, FNSOX dropped -8.92% vs FXNAX's -19.51%.

Which has better risk-adjusted returns?

FNSOX currently has the higher Sharpe Ratio (1.57 vs 1.14), 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.