FNSOX vs. FNILX

Last updated Jun 4, 2026

FNSOX (Fidelity Short-Term Bond Index Fund) and FNILX (Fidelity ZERO Large Cap Index Fund) are both mutual funds - FNSOX is a Total Bond Market fund managed by Fidelity, while FNILX is a Large Cap Blend Equities fund managed by Fidelity. Over the past 5 years, FNSOX returned 1.62%/yr vs 14.13%/yr for FNILX. At a correlation of -0.00, they often move in opposite directions. FNSOX charges 0.03%/yr vs 0.00%/yr for FNILX.

Performance

FNSOX vs. FNILX - Performance Comparison

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

Returns By Period

In the year-to-date period, FNSOX achieves a 0.37% return, which is significantly lower than FNILX's 11.56% return.

FNSOX

• 1D: 0.00%
• 1M: 0.17%
• YTD: 0.37%
• 6M: 0.62%
• 1Y: 3.77%
• 3Y*: 4.48%
• 5Y*: 1.62%
• 10Y*: —

FNILX

• 1D: 0.26%
• 1M: 6.04%
• YTD: 11.56%
• 6M: 11.44%
• 1Y: 28.65%
• 3Y*: 23.01%
• 5Y*: 14.13%
• 10Y*: —

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

FNSOX vs. FNILX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018
FNSOX Fidelity Short-Term Bond Index Fund	0.37%	6.01%	3.90%	4.90%	-5.76%	-1.25%	4.28%	4.95%	1.43%
FNILX Fidelity ZERO Large Cap Index Fund	11.56%	17.81%	25.47%	27.45%	-19.37%	26.67%	21.13%	31.79%	-13.60%

Correlation

The correlation between FNSOX and FNILX is 0.17, which is low. Their price movements are largely independent, making them effective diversification partners.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.17
Correlation (3Y) Calculated over the trailing 3-year period	0.12
Correlation (5Y) Calculated over the trailing 5-year period	0.10
Correlation (All Time) Calculated using the full available price history since Oct 1, 2018	-0.00

The correlation between FNSOX and FNILX shifts across timeframes, from -0.00 (all time) to 0.17 (1 year), reflecting how their relationship changes across market environments.

Return for Risk

FNSOX vs. FNILX — Risk / Return Rank

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

FNSOX

FNSOX Risk / Return Rank: 44
FNSOX Sharpe Ratio Rank: 40
FNSOX Sortino Ratio Rank: 50
FNSOX Omega Ratio Rank: 47
FNSOX Calmar Ratio Rank: 45
FNSOX Martin Ratio Rank: 40

FNILX

FNILX Risk / Return Rank: 71
FNILX Sharpe Ratio Rank: 73
FNILX Sortino Ratio Rank: 65
FNILX Omega Ratio Rank: 64
FNILX Calmar Ratio Rank: 72
FNILX Martin Ratio Rank: 80

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. FNILX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Short-Term Bond Index Fund (FNSOX) and Fidelity ZERO Large Cap Index Fund (FNILX). 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	FNILX	Difference
Sharpe ratio: Return per unit of total volatility	1.83	2.48	-0.65
Sortino ratio: Return per unit of downside risk	2.99	3.36	-0.37
Omega ratio: Gain probability vs. loss probability	1.37	1.45	-0.08
Calmar ratio: Return relative to maximum drawdown	2.57	3.28	-0.71
Martin ratio: Return relative to average drawdown	8.53	15.01	-6.49
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. FNILX - Sharpe Ratio Comparison

The current FNSOX Sharpe Ratio is 1.83, which is comparable to the FNILX Sharpe Ratio of 2.48. The chart below compares the historical Sharpe Ratios of FNSOX and FNILX, 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	FNILX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	1.83	2.48	-0.65
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.56	0.82	-0.26
Sharpe Ratio (All Time) Calculated using the full available price history	0.84	0.76	+0.08

Drawdowns

FNSOX vs. FNILX - Drawdown Comparison

The maximum FNSOX drawdown since its inception was -8.92%, smaller than the maximum FNILX drawdown of -33.76%. Use the drawdown chart below to compare losses from any high point for FNSOX and FNILX.

Drawdown Indicators

	FNSOX	FNILX	Difference
Max Drawdown Largest peak-to-trough decline	-8.92%	-33.76%	+24.84%
Max Drawdown (1Y) Largest decline over 1 year	-1.47%	-9.01%	+7.54%
Max Drawdown (3Y) Largest decline over 3 years	-1.51%	-19.08%	+17.57%
Max Drawdown (5Y) Largest decline over 5 years	-8.77%	-25.40%	+16.63%
Current Drawdown Current decline from peak	-0.60%	0.00%	-0.60%
Average Drawdown Average peak-to-trough decline	-1.73%	-5.37%	+3.64%
Ulcer Index Depth and duration of drawdowns from previous peaks	0.44%	1.97%	-1.53%

Volatility

FNSOX vs. FNILX - Volatility Comparison

The current volatility for Fidelity Short-Term Bond Index Fund (FNSOX) is 0.68%, while Fidelity ZERO Large Cap Index Fund (FNILX) has a volatility of 2.88%. This indicates that FNSOX experiences smaller price fluctuations and is considered to be less risky than FNILX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FNSOX	FNILX	Difference
Volatility (1M) Calculated over the trailing 1-month period	0.68%	2.88%	-2.20%
Volatility (6M) Calculated over the trailing 6-month period	1.51%	8.99%	-7.48%
Volatility (1Y) Calculated over the trailing 1-year period	2.07%	11.93%	-9.86%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	2.89%	17.25%	-14.36%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	2.47%	20.04%	-17.57%

FNSOX vs. FNILX - Expense Ratio Comparison

FNSOX has a 0.03% expense ratio, which is higher than FNILX's 0.00% 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. FNILX - Dividend Comparison

FNSOX's dividend yield for the trailing twelve months is around 3.53%, more than FNILX's 0.91% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017
FNILX Fidelity ZERO Large Cap Index Fund	0.91%	1.01%	1.09%	1.34%	1.53%	0.95%	1.20%	1.17%	0.53%	0.00%
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%

Frequently Asked Questions

Can I hold both FNSOX and FNILX in my portfolio?

FNSOX and FNILX have a correlation of 0.17, 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 FNILX?

FNILX has higher volatility (2.88%) compared to FNSOX (0.68%). In terms of maximum drawdown, FNSOX dropped -8.92% vs FNILX's -33.76%.

Which has better risk-adjusted returns?

FNILX currently has the higher Sharpe Ratio (2.48 vs 1.83), 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.