Rush Street Interactive, Inc.

1. On March 2, 2026, the Reporting Person exchanged, pursuant to the Amended and Restated Limited Partnership Agreement of Rush Street Interactive, LP ("RSI LP"), 50,000 Class A Common Stock Units ("RSI Units") for 50,000 shares of Class A Common Stock of the Issuer, together with an equivalent number of Class V Voting Stock of the Issuer held by the Reporting Person being canceled.

2. The Reporting Person disclaims beneficial ownership of the reported securities except to the extent of his pecuniary interest therein, and this report shall not be deemed an admission that such securities are beneficially owned by the Reporting Person for Section 16 or any other purpose.

3. The shares of Class V Voting Stock of the Issuer provide no economic rights in the Issuer to the holder thereof. However, each holder of Class V Voting Stock will be entitled to vote as a common stockholder of the Issuer, with the number of votes equal to the number of shares of Class V Voting Stock held at the time of such vote.

4. Shares were sold pursuant to a 10b5-1 plan.

5. The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $20.00 to $20.04 per share. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

6. The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $19.29 to $20.04 per share. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

7. The reported price in Column 4 is a weighted average sale price. These shares were sold in multiple transactions at prices ranging from $20.00 to $20.46 per share. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

8. Pursuant to the Amended and Restated Limited Partnership Agreement of RSI LP, beginning on June 29, 2021, the RSI Units beneficially owned by the reporting person may be exchanged, subject to certain conditions, for one share of Class A Common Stock of the Issuer. Upon such exchange, an equivalent number of shares of Class V Voting Stock then held by the reporting person will be canceled.