BSPIX vs. WFSPX

Last updated Jun 4, 2026

BSPIX (iShares S&P 500 Index Fund Institutional Class) and WFSPX (iShares S&P 500 Index Fund) are both S&P 500 funds tracking the S&P 500 Index, from iShares and BlackRock respectively. Both are passively managed. Over the past 10 years, BSPIX returned 15.46%/yr vs 15.54%/yr for WFSPX. With a 1.00 correlation, they move nearly in lockstep. BSPIX charges 0.10%/yr vs 0.03%/yr for WFSPX.

Performance

BSPIX vs. WFSPX - Performance Comparison

The chart below illustrates the hypothetical performance of a $10,000 investment in iShares S&P 500 Index Fund Institutional Class (BSPIX) and iShares S&P 500 Index Fund (WFSPX). The values are adjusted to include any dividend payments, if applicable.

Returns By Period

The year-to-date returns for both investments are quite close, with BSPIX having a 11.65% return and WFSPX slightly higher at 11.69%. Both investments have delivered pretty close results over the past 10 years, with BSPIX having a 15.46% annualized return and WFSPX not far ahead at 15.54%.

BSPIX

• 1D: 0.13%
• 1M: 5.79%
• YTD: 11.65%
• 6M: 11.68%
• 1Y: 28.84%
• 3Y*: 22.63%
• 5Y*: 14.17%
• 10Y*: 15.46%

WFSPX

• 1D: 0.13%
• 1M: 5.80%
• YTD: 11.69%
• 6M: 11.72%
• 1Y: 28.93%
• 3Y*: 22.71%
• 5Y*: 14.24%
• 10Y*: 15.54%

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

BSPIX vs. WFSPX - Yearly Performance Comparison

	2026 (YTD)	2025	2024	2023	2022	2021	2020	2019	2018	2017
BSPIX iShares S&P 500 Index Fund Institutional Class	11.65%	17.75%	24.85%	26.17%	-18.20%	28.55%	18.35%	31.35%	-4.87%	21.20%
WFSPX iShares S&P 500 Index Fund	11.69%	17.83%	24.94%	26.25%	-18.14%	28.63%	18.43%	31.45%	-4.83%	21.27%

Correlation

The correlation between BSPIX and WFSPX is 1.00 - these two move nearly in lockstep. At this level, holding both provides almost no diversification benefit. If you already own one, adding the other does little to reduce portfolio risk.

	Correlation
Correlation (1Y) Calculated over the trailing 1-year period	1.00
Correlation (3Y) Calculated over the trailing 3-year period	1.00
Correlation (5Y) Calculated over the trailing 5-year period	1.00
Correlation (10Y) Calculated over the trailing 10-year period	1.00
Correlation (All Time) Calculated using the full available price history since Jan 3, 2014	1.00

The correlation between BSPIX and WFSPX has been stable across timeframes, ranging from 1.00 to 1.00 - a consistent structural relationship.

Return for Risk

BSPIX vs. WFSPX — Risk / Return Rank

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

BSPIX

BSPIX Risk / Return Rank: 73
BSPIX Sharpe Ratio Rank: 74
BSPIX Sortino Ratio Rank: 67
BSPIX Omega Ratio Rank: 67
BSPIX Calmar Ratio Rank: 74
BSPIX Martin Ratio Rank: 83

WFSPX

WFSPX Risk / Return Rank: 73
WFSPX Sharpe Ratio Rank: 75
WFSPX Sortino Ratio Rank: 67
WFSPX Omega Ratio Rank: 67
WFSPX Calmar Ratio Rank: 74
WFSPX Martin Ratio Rank: 83

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.

BSPIX vs. WFSPX - Risk-Adjusted Trends Comparison

This table presents a comparison of risk-adjusted performance metrics for iShares S&P 500 Index Fund Institutional Class (BSPIX) and iShares S&P 500 Index Fund (WFSPX). 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.

	BSPIX	WFSPX	Difference
Sharpe ratio Return per unit of total volatility	2.51	2.52	-0.01
Sortino ratio Return per unit of downside risk	3.41	3.42	-0.01
Omega ratio Gain probability vs. loss probability	1.46	1.46	0.00
Calmar ratio Return relative to maximum drawdown	3.34	3.35	-0.01
Martin ratio Return relative to average drawdown	15.58	15.65	-0.07
Data is calculated on a 1-year rolling basis and updated daily. The trend shows the change in the indicator over the past month.

BSPIX vs. WFSPX - Sharpe Ratio Comparison

The current BSPIX Sharpe Ratio is 2.51, which is comparable to the WFSPX Sharpe Ratio of 2.52. The chart below compares the historical Sharpe Ratios of BSPIX and WFSPX, 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

	BSPIX	WFSPX	Difference
Sharpe Ratio (1Y) Calculated over the trailing 1-year period	2.51	2.52	-0.01
Sharpe Ratio (5Y) Calculated over the trailing 5-year period	0.84	0.85	0.00
Sharpe Ratio (10Y) Calculated over the trailing 10-year period	0.86	0.87	0.00
Sharpe Ratio (All Time) Calculated using the full available price history	0.81	0.13	+0.68

Drawdowns

BSPIX vs. WFSPX - Drawdown Comparison

The maximum BSPIX drawdown since its inception was -33.75%, smaller than the maximum WFSPX drawdown of -58.21%. Use the drawdown chart below to compare losses from any high point for BSPIX and WFSPX.

Drawdown Indicators

	BSPIX	WFSPX	Difference
Max Drawdown Largest peak-to-trough decline	-33.75%	-58.21%	+24.46%
Max Drawdown (1Y) Largest decline over 1 year	-8.91%	-8.90%	-0.01%
Max Drawdown (3Y) Largest decline over 3 years	-18.74%	-18.74%	0.00%
Max Drawdown (5Y) Largest decline over 5 years	-24.55%	-24.51%	-0.04%
Max Drawdown (10Y) Largest decline over 10 years	-33.75%	-33.74%	-0.01%
Current Drawdown Current decline from peak	0.00%	0.00%	0.00%
Average Drawdown Average peak-to-trough decline	-3.93%	-12.77%	+8.84%
Ulcer Index Depth and duration of drawdowns from previous peaks	1.90%	1.90%	0.00%

Volatility

BSPIX vs. WFSPX - Volatility Comparison

iShares S&P 500 Index Fund Institutional Class (BSPIX) and iShares S&P 500 Index Fund (WFSPX) have volatilities of 2.83% and 2.82%, respectively, indicating that both stocks experience similar levels of price fluctuations. This suggests that the risk associated with both stocks, as measured by volatility, is nearly the same. The chart below showcases a comparison of their rolling one-month volatility.

Volatility by Period

	BSPIX	WFSPX	Difference
Volatility (1M) Calculated over the trailing 1-month period	2.83%	2.82%	+0.01%
Volatility (6M) Calculated over the trailing 6-month period	8.97%	8.97%	0.00%
Volatility (1Y) Calculated over the trailing 1-year period	11.85%	11.85%	0.00%
Volatility (5Y) Calculated over the trailing 5-year period, annualized	16.88%	16.88%	0.00%
Volatility (10Y) Calculated over the trailing 10-year period, annualized	18.03%	18.02%	+0.01%

BSPIX vs. WFSPX - Expense Ratio Comparison

BSPIX has a 0.10% expense ratio, which is higher than WFSPX'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

BSPIX vs. WFSPX - Dividend Comparison

BSPIX's dividend yield for the trailing twelve months is around 1.50%, less than WFSPX's 1.56% yield.

Position	TTM	2025	2024	2023	2022	2021	2020	2019	2018	2017	2016	2015
BSPIX iShares S&P 500 Index Fund Institutional Class	1.50%	1.66%	1.35%	1.44%	1.94%	1.76%	1.60%	1.92%	1.94%	1.57%	2.30%	2.42%
WFSPX iShares S&P 500 Index Fund	1.56%	1.72%	1.41%	1.50%	2.02%	1.82%	1.66%	1.99%	2.00%	1.62%	2.37%	2.49%

Frequently Asked Questions

Can I hold both BSPIX and WFSPX in my portfolio?

With a correlation of 1.00, BSPIX and WFSPX move almost identically. Holding both adds very little diversification - you're essentially doubling your position in the same market segment. Choosing one is usually more capital-efficient.

Which is riskier, BSPIX or WFSPX?

BSPIX has higher volatility (2.83%) compared to WFSPX (2.82%). In terms of maximum drawdown, BSPIX dropped -33.75% vs WFSPX's -58.21%.

Which has better risk-adjusted returns?

WFSPX currently has the higher Sharpe Ratio (2.52 vs 2.51), 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.