Fund Evaluator:

SEI Extended Market Index A (SIIT) Overview

SEI Extended Market Index A (SIIT) (SMXAX) is a passively managed U.S. Equity Mid-Cap Blend fund. SEI launched the fund in 2013.

The investment seeks results that approximate, as closely as practicable and before expenses, the performance of the Russell Small Cap Completeness Index. The fund is managed using a passive/indexing investment approach and invests substantially all of its assets in securities (mostly common stocks) of companies that are included in the Russell Small Cap Completeness Index. The index is composed of securities of the companies included in the Russell 3000 Index (which includes the largest 3,000 U.S. companies), excluding the securities of companies that are constituents of the S&P 500 Index (which includes 500 leading U.S. companies).

About SEI Extended Market Index A (SIIT) (SMXAX)

There are 6 members of the management team with an average tenure of 6.88 years: Jason Collins (2016), Emiliano Rabinovich (2023), David Hintz (2024), Amy Scofield (2013), Ryan McKeon (2024), Karl Schneider (2013). Management tenure is more important for actively managed funds than passive index funds.

The fund has 2 primary benchmarks: S&P 500 (TR) (1970) index with a weighting of 100% and Russell Small Cap Complete TR USD index with a weighting of 100%. SEI Extended Market Index A (SIIT) has 2341 securities in its portfolio. The top 10 holdings constitute 8.4% of the fund’s assets. The fund meets the SEC requirement of being classified as a diversified fund. The fund is not considered to have an ESG focus with its investment selection and management.

SEI Extended Market Index A (SIIT) is part of the Equity global asset class and is within the U.S. Equity fund group. SEI Extended Market Index A (SIIT) has 3.0% of its portfolio invested in foreign issues. The overall assets allocated to domestic stock is 95.9%. There is 3.0% allocated to foreign stock, and 0.0% is allocated to preferred stocks. The bond allocation as a percentage of total assets is 0.0% (0.0% domestic bond, 0.0% foreign bond and 0.0% convertible bond). SEI Extended Market Index A (SIIT) has 1.2% of the portfolio in cash.

Assets Under Management

The fund has $1 billion in total assets, which is below the $1 billion average for the Mid-Cap Blend category. Normally, lower assets under management translates to higher average expense ratios, and greater total assets are desired. However, for some investment categories, such as small-cap investing, it may be difficult for the manager to fully employ the desired active strategy if assets grow too large or too quickly.

SMXAX Performance and Fees

The expense ratio measures how much of a fund’s assets are used for administrative expenses and operating expenses, including adviser fees and fees for the transfer agent and custodial services. The SEI Extended Market Index A (SIIT) expense ratio is low compared to funds in the Mid-Cap Blend category. SEI Extended Market Index A (SIIT) has an expense ratio of 0.06%, which is 94% lower than its category average, making the fund expense ratio grade a A. While it is difficult to predict returns, it is known that high annual expense ratios reduce your rate of return, and excessive fees are difficult to overcome. Active management normally comes with higher expense ratios than passive index management. Certain investment categories such as small company and foreign also normally have higher expense ratios. It is best to compare fund expense ratios against the category averages for meaningful assessments.

High portfolio turnover can translate to higher expenses and lower aftertax returns. SEI Extended Market Index A (SIIT) has a portfolio turnover rate of 21%, indicating that holds its assets around 0.0 years. By way of comparison, the average portfolio turnover is 51% for the Mid-Cap Blend category.

Recently, in the month of July 2026, SEI Extended Market Index A (SIIT) returned -3.8%, which earned it a grade of D, as the Mid-Cap Blend category had an average return of -1.8%. The letter grades of A, B, C, D and F are based upon relative rankings within the investment category. A grade of A, for example, would indicate that the return is in the highest 20% for that time period compared to all funds in that category.

SEI Extended Market Index A (SIIT) has a trailing yield of 1.07%, which is above the 0.48% category average. The fund normally distributes its income quarterly and its capital gains annually.

It’s natural to seek the best-performing investments, but you must consider the relationship between risk and return and the impact of costs and taxes on your realized returns.

SEI Extended Market Index A (SIIT) Grades

Year to date, the fund has returned 13.4%, 0.3 percentage points better than the category, which translates into a grade of C. The fund has returned 21.5% over the past year (grade of B), 16.1% over the past three years (grade of A) and 6.7% per year over the past five years (grade of D) and 11.9% per year over the past 10 years (grade of A).

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