FSOSX vs. FSKAX

Last updated Jun 4, 2026

FSOSX (Fidelity Series Overseas Fund) and FSKAX (Fidelity Total Market Index Fund) are both mutual funds - FSOSX is a Foreign Large Cap Equities fund managed by Fidelity, while FSKAX is a Large Cap Blend Equities fund managed by Fidelity. Over the past 5 years, FSOSX returned 6.73%/yr vs 13.08%/yr for FSKAX. A 0.79 correlation means they provide meaningful diversification when combined. FSOSX charges 0.01%/yr vs 0.01%/yr for FSKAX.

Performance

FSOSX vs. FSKAX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in Fidelity Series Overseas Fund (FSOSX) and Fidelity Total Market Index Fund (FSKAX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

In the year-to-date period, FSOSX achieves a 5.63% return, which is significantly lower than FSKAX's 12.08% return.

FSOSX

• 1D: 0.96%
• 1M: 3.89%
• YTD: 5.63%
• 6M: 7.55%
• 1Y: 8.98%
• 3Y*: 13.16%
• 5Y*: 6.73%
• 10Y*: —

FSKAX

• 1D: 0.24%
• 1M: 5.80%
• YTD: 12.08%
• 6M: 11.98%
• 1Y: 29.13%
• 3Y*: 22.42%
• 5Y*: 13.08%
• 10Y*: 15.09%

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

FSOSX vs. FSKAX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019
FSOSX Fidelity Series Overseas Fund	5.63%	21.29%	5.87%	21.49%	-23.25%	19.59%	16.36%	7.78%
FSKAX Fidelity Total Market Index Fund	12.08%	17.06%	23.89%	26.12%	-19.53%	25.66%	20.79%	10.30%

Correlation

The correlation between FSOSX and FSKAX is 0.79, which is moderate. They share some common price drivers but move independently often enough to provide real diversification benefit when combined.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	0.79
Correlation (3Y) Calculated over the trailing 3-year period	0.76
Correlation (5Y) Calculated over the trailing 5-year period	0.78
Correlation (All Time) Calculated using the full available price history since Jul 1, 2019	0.79

The correlation between FSOSX and FSKAX has been stable across timeframes, ranging from 0.76 to 0.79 - a consistent structural relationship.

Return for Risk

FSOSX vs. FSKAX — Risk / Return Rank

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

FSOSX

FSOSX Risk / Return Rank: 7
FSOSX Sharpe Ratio Rank: 6
FSOSX Sortino Ratio Rank: 6
FSOSX Omega Ratio Rank: 6
FSOSX Calmar Ratio Rank: 7
FSOSX Martin Ratio Rank: 8

FSKAX

FSKAX Risk / Return Rank: 71
FSKAX Sharpe Ratio Rank: 71
FSKAX Sortino Ratio Rank: 64
FSKAX Omega Ratio Rank: 63
FSKAX Calmar Ratio Rank: 74
FSKAX Martin Ratio Rank: 82

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.

FSOSX vs. FSKAX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for Fidelity Series Overseas Fund (FSOSX) and Fidelity Total Market Index Fund (FSKAX). 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.

	FSOSX	FSKAX	Difference
Sharpe ratio Return per unit of total volatility	0.50	2.46	-1.96
Sortino ratio Return per unit of downside risk	0.83	3.35	-2.52
Omega ratio Gain probability vs. loss probability	1.10	1.44	-0.34
Calmar ratio Return relative to maximum drawdown	0.68	3.38	-2.70
Martin ratio Return relative to average drawdown	2.42	15.52	-13.10
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

FSOSX vs. FSKAX - Sharpe Ratio Comparison

The current FSOSX Sharpe Ratio is 0.50, which is lower than the FSKAX Sharpe Ratio of 2.46. The chart below compares the historical Sharpe Ratios of FSOSX and FSKAX, 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

	FSOSX	FSKAX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	0.50	2.46	-1.96
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.38	0.76	-0.37
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	—	0.82	—
Sharpe Ratio (All Time) Calculated using the full available price history	0.51	0.85	-0.34

Drawdowns

FSOSX vs. FSKAX - Drawdown Comparison

The maximum FSOSX drawdown since its inception was -35.36%, roughly equal to the maximum FSKAX drawdown of -35.01%. Use the drawdown chart below to compare losses from any high point for FSOSX and FSKAX.

Drawdown Indicators

	FSOSX	FSKAX	Difference
Max Drawdown Largest peak-to-trough decline	-35.36%	-35.01%	-0.35%
Max Drawdown (1Y) Largest decline over 1 year	-12.39%	-8.92%	-3.47%
Max Drawdown (3Y) Largest decline over 3 years	-14.07%	-19.43%	+5.36%
Max Drawdown (5Y) Largest decline over 5 years	-35.36%	-25.39%	-9.97%
Max Drawdown (10Y) Largest decline over 10 years	—	-35.01%	—
Current Drawdown Current decline from peak	-1.31%	0.00%	-1.31%
Average Drawdown Average peak-to-trough decline	-7.78%	-4.02%	-3.76%
Ulcer Index Depth and duration of drawdowns from previous peaks	3.46%	1.94%	+1.52%

Volatility

FSOSX vs. FSKAX - Volatility Comparison

Fidelity Series Overseas Fund (FSOSX) has a higher volatility of 6.14% compared to Fidelity Total Market Index Fund (FSKAX) at 2.97%. This indicates that FSOSX's price experiences larger fluctuations and is considered to be riskier than FSKAX based on this measure. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	FSOSX	FSKAX	Difference
Volatility (1M) Calculated over the trailing 1-month period	6.14%	2.97%	+3.17%
Volatility (6M) Calculated over the trailing 6-month period	14.30%	9.23%	+5.07%
Volatility (1Y) Calculated over the trailing 1-year period	16.80%	12.26%	+4.54%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	17.67%	17.41%	+0.26%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	19.05%	18.46%	+0.59%

FSOSX vs. FSKAX - Expense Ratio Comparison

FSOSX has a 0.01% expense ratio, which is lower than FSKAX's 0.02% 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

FSOSX vs. FSKAX - Dividend Comparison

FSOSX's dividend yield for the trailing twelve months is around 8.66%, more than FSKAX's 0.93% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
FSKAX Fidelity Total Market Index Fund	0.93%	1.01%	1.19%	1.41%	1.62%	1.15%	1.45%	1.94%	2.54%	2.07%	2.43%	0.82%
FSOSX Fidelity Series Overseas Fund	8.66%	9.15%	2.25%	1.63%	1.80%	2.92%	1.12%	0.37%	0.00%	0.00%	0.00%	0.00%

Frequently Asked Questions

Can I hold both FSOSX and FSKAX in my portfolio?

FSOSX and FSKAX have a correlation of 0.79, meaning they provide meaningful diversification benefit when combined. Depending on your allocation goals, holding both could reduce overall portfolio risk.

Which is riskier, FSOSX or FSKAX?

FSOSX has higher volatility (6.14%) compared to FSKAX (2.97%). In terms of maximum drawdown, FSOSX dropped -35.36% vs FSKAX's -35.01%.

Which has better risk-adjusted returns?

FSKAX currently has the higher Sharpe Ratio (2.46 vs 0.50), 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.