| 2024 | Plein Family Foundation | 990PF | President & Board Chair | 2 | $0 | $0 | View return |
| 2024 | Mason Housing Inc | 990 | Director | 1 | $0 | $0 | View return |
| 2024 | White House Farm Foundation C/O Scott C Plein | 990PF | President/Board Chairman/Director | 2 | $0 | $0 | View return |
| 2024 | Potomac Riverkeeper Network | 990 | Director | 1 | $0 | $0 | View return |
| 2023 | Plein Family Foundation | 990PF | President & Board Chair | 2 | $0 | $0 | View return |
| 2023 | White House Farm Foundation C/O Scott C Plein | 990PF | President/Board Chairman/Director | 2 | $0 | $0 | View return |
| 2023 | Mason Housing Inc | 990 | Director | 1 | $0 | $0 | View return |
| 2023 | American Horticultural Society Inc. | 990 | Chairman | 5 | $0 | $0 | View return |
| 2023 | Northern Virginia Transportation Education Foundation | 990 | Board Member | 1 | $0 | $0 | View return |
| 2022 | Mason Housing Inc | 990 | Director | 1 | $0 | $0 | View return |
| 2022 | Potomac Riverkeeper Network | 990 | Director | 2 | $0 | $0 | View return |
| 2022 | White House Farm Foundation C/O Scott C Plein | 990PF | President/Board Chairman/Director | 2 | $0 | $0 | View return |
| 2022 | Northern Virginia Transportation Education Foundation | 990 | Board Member | 1 | $0 | $0 | View return |
| 2022 | American Horticultural Society Inc. | 990 | Chairman | 5 | $0 | $0 | View return |
| 2021 | Northern Virginia Transportation Education Foundation | 990 | Board Member | 1 | $0 | $0 | View return |
| 2021 | Mason Housing Inc | 990 | Director | 1 | $0 | $0 | View return |
| 2021 | White House Farm Foundation C/O Scott C Plein | 990PF | President/Board Chairman/Director | 2 | $0 | $0 | View return |
| 2021 | Potomac Riverkeeper Network | 990 | Treasurer | 2 | $0 | $0 | View return |
| 2021 | American Horticultural Society Inc. | 990 | Director | 1 | $0 | $0 | View return |
| 2020 | Potomac Riverkeeper Network | 990 | Treasurer | 2 | $0 | $0 | View return |
| 2020 | Mason Housing Inc | 990 | Director | 1 | $0 | $0 | View return |
| 2020 | White House Farm Foundation C/O Scott C Plein | 990PF | President/Board Chairman/Director | 2 | $0 | $0 | View return |
| 2020 | Northern Virginia Transportation Education Foundation | 990 | Board Member | 1 | $0 | $0 | View return |
| 2019 | Potomac Riverkeeper Network | 990 | Treasurer | 2 | $0 | $0 | View return |
| 2019 | Mason Housing Inc | 990 | Director | 1 | $0 | $0 | View return |
| 2019 | Northern Virginia Transportation Education Foundation | 990 | Board Member | 1 | $0 | $0 | View return |
| 2018 | Mason Housing Inc | 990 | Director | 1 | $0 | $0 | View return |
| 2018 | Potomac Riverkeeper Network | 990 | Treasurer | 2 | $0 | $0 | View return |
| 2018 | White House Farm Foundation C/O Scott C Plein | 990PF | President/Director/Board Chairman | 2 | $0 | $0 | View return |
| 2018 | Northern Virginia Transportation Education Foundation | 990 | Board Member | 1 | $0 | $0 | View return |
| 2017 | Mason Housing Inc | 990 | Director | 1 | $0 | $0 | View return |
| 2017 | Northern Virginia Transportation Education Foundation | 990 | Board Member | 1 | $0 | $0 | View return |
| 2017 | Potomac Riverkeeper Network | 990 | Treasurer | 2 | $0 | $0 | View return |
| 2017 | White House Farm Foundation C/O Scott C Plein | 990PF | Director/Board Chairman | 4 | $0 | $0 | View return |
| 2016 | Mason Housing Inc | 990 | Director | 1 | $0 | $0 | View return |
| 2016 | White House Farm Foundation C/O Scott C Plein | 990PF | Director/Board Chairman | 4 | $0 | $0 | View return |
| 2016 | Northern Virginia Transportation Education Foundation | 990 | Board Member | 1 | $0 | $0 | View return |
| 2016 | Asian American Success Incorporated | 990EZ | Board Member | 1 | $0 | - | View return |
| 2016 | Potomac Riverkeeper Network | 990 | Treasurer | 1 | $0 | $0 | View return |
| 2015 | Dulles South Alliance | 990EZ | Director | 1 | $0 | - | View return |
| 2015 | Potomac Riverkeeper Network | 990 | Director | 1 | $0 | $0 | View return |
| 2015 | Mason Housing Inc | 990 | Director | 1 | $0 | $0 | View return |
| 2015 | Northern Virginia Transportation Education Foundation | 990 | Board Member | 1 | $0 | $0 | View return |
| 2015 | White House Farm Foundation C/O Scott C Plein | 990PF | Director/Board Chairman | 4 | $0 | $0 | View return |
| 2014 | Northern Virginia Building Industry Association Inc | 990 | Senior Life Directors | 1 | $0 | $0 | View return |
| 2014 | Mason Housing Inc | 990 | Director | 1 | - | - | View return |
| 2014 | Hopkins House-A Center for Children and Their Families | 990 | Trustee | 8 | $0 | $0 | View return |
| 2014 | White House Farm Foundation C/O Scott C Plein | 990PF | Director/Board Chairman | 4 | $0 | $0 | View return |
| 2013 | Northern Virginia Building Industry Association Inc | 990 | Senior Life Directors | 1 | $0 | $0 | View return |
| 2013 | White House Farm Foundation C/O Scott C Plein | 990PF | Director/Board Chairman | 4 | $0 | $0 | View return |
| 2013 | Asian American Success Incorporated | 990EZ | Director | 1 | $0 | - | View return |
| 2013 | Northern Virginia Transportation Education Foundation | 990 | Board Member | 1 | $0 | $0 | View return |
| 2012 | White House Farm Foundation C/O Scott C Plein | 990PF | Director/Board Chairman | 4 | $0 | $0 | View return |
| 2011 | White House Farm Foundation C/O Scott C Plein | 990PF | Director/Board Chairman | 4 | $0 | $0 | View return |