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Philosophical Society of Washington

EIN 52-1073697 · Washington, DC

Public records show a registered, tax-exempt organization in good standing.

LegitimacyPassesRegistration and standingFinancial healthStrong100 out of 100GovernanceFair62 out of 100Impact evidenceDescribes programsHow well its results are evidenced

What it says it does

Educational, scientific, and professional society organized in 1871 by Joseph Henry (the first secretary of the Smithsonian) providing science lectures, education, and discussion to its members and the public for the promotion of science, the advancement of learning, and the free exchange of views among its members and attendees on scientific subjects. Lectures and the accompanying discussion are recorded and made available to all, free of charge, on the Society's video channels.

Income
$160,997
Spending
$116,162
Spent on programs
88%
Reserves
57.4 months of spending
Largest source of income
donations and private grants, 46%
Employees
0
Volunteers
20

Source: Form 990 for the year ending June 30, 2025, filed with the Internal Revenue Service. Rating method 2026.2. How we rate

Financial health

Strong: 100 out of 100.

  • Reserves

    35 of 35

    Spendable reserves would cover 57.4 months of spending.

  • Debt

    20 of 20

    It owes 3% of what it owns.

  • Living within its means

    15 of 15

    Income exceeded spending by 28% of income.

  • Income trend

    15 of 15

    Income rose 21% on the year before.

  • Spending floor

    15 of 15

    88% of spending went to programs and raising each dollar of donations cost 2 cents.

Source: Form 990 for the year ending June 30, 2025, filed with the Internal Revenue Service. Rating method 2026.2. How we rate

Governance

Fair: 62 out of 100.

  • Independent board

    25 of 25

    9 of 9 voting board members are independent.

  • Conflict of interest policy

    0 of 15

    Reports no written conflict of interest policy.

  • Whistleblower policy

    0 of 8

    Reports no written whistleblower policy.

  • Record keeping policy

    0 of 7

    Reports no written policy on keeping and destroying records.

  • Board minutes

    5 of 5

    Keeps minutes of board meetings.

  • Board sees the tax return

    10 of 10

    Gave the board a copy of this return before filing it.

  • No reported misuse

    10 of 10

    Reports no diversion of assets, excess benefits or loans to insiders.

Source: Form 990 for the year ending June 30, 2025, filed with the Internal Revenue Service. Rating method 2026.2. How we rate

Impact evidence

Describes programs. Its tax return describes what it does but we have found no measurable results in it.

Programs described in its return (2)
  1. $87,895 spent. PSW Science is one of the oldest scientific societies in Washington, DC founded in 1871 by Joseph Henry, the first Secretary of the Smithsonian Institution. It presents 16-20 science lectures a year, free and open to the public with discussion during and after the lecture. Approximately 1200 to 1500 people attend each year; individual lecture attendance is approximately 80-200. There is a pre-lecture reception and dinner with the speaker before the lecture; dinner attendees pay an event fee to cover costs; attendance is 20-50 per lecture. The receptions and dinners are designed to provide ample opportunity for interaction among the attendees with the speaker, and many collaborations have been initiated at these gatherings. The lectures address the scientific issues of the day and there is robust discussion before, during, and after the lecture. The lecturers are usually leading scientists in the field or leaders of important scientific organizations. The lectures are in-depth and sophisticated, about an hour in length followed by a robust question and answer period of approximately 30 to 60 minutes. The lectures are geared to address three levels of discourse: professional scientists in the field of the lecturer, scientists in other fields, and others who are interested in the topic but are not scientific specialists. The lectures are not basic summaries or short popular-style snippets of information, but are designed to address the substantive technical nature of the work being presented. PSW Science has a strong interdisciplinary educational mission to bring together scientists and others who work in diverse fields and diverse institutions of academia, industry, and government so that they will benefit from discussion with others outside of their fields and institutions. PSW Science engages all areas of science, including both physical and life science, with lectures in the areas of astronomy, planetary and earth science, cosmology, biomedical science, chemistry and biochemistry, computer science, artificial intelligence, biology, and engineering, to name just a few. Members and regular attendees work in industry, government, and academia. Many members and regular attendees work for or with federal agencies, such as NASA, NIST, NSF, DOE, and NIH. Members and regular attendees include students, young-career professionals, and established scientists. One of the primary goals of PSW Science is to provide an opportunity for students and younger professionals to meet and interact with prominent scientists.
  2. $14,027 spent. PSW Science's educational outreach is substantial and multi-faceted. It live-streams its science lectures and posts them to its website and PSW Science YouTube and Vimeo channels, where the videos have been viewed over a million times. In addition, approximately 20-100 people watch each live stream and participate in real-time in the discussion. There are hundreds of thousands of views of the lectures each year on the PSW Science channels with viewers located throughout the world. These viewers have the opportunity to see leading scientists in a field discuss the most important scientific issues of the day. This is a core part of the mission of PSW Science -- to provide science education to as many people as possible without charge.

Source: Form 990 for the year ending June 30, 2025, filed with the Internal Revenue Service. Rating method 2026.2. How we rate

Legitimacy checks

  1. Is it registered with the IRS? Passed.

    Listed in the IRS master file of tax-exempt organizations as a 501(c)(3) charitable organization.

    Source: Exempt Organizations Business Master File, Internal Revenue Service, file dated October 13, 2026.

  2. Has the IRS revoked its tax-exempt status? Passed.

    Not on the IRS automatic revocation list.

    Source: Automatic revocation of exemption list, Internal Revenue Service, file dated October 13, 2026.

  3. Are donations tax-deductible? Passed.

    On the IRS list of organizations eligible to receive tax-deductible contributions.

    Source: Publication 78 data: organizations eligible for tax-deductible contributions, Internal Revenue Service, file dated October 13, 2026.

  4. Is it keeping up with its IRS filings? Passed.

    Most recent return on file covers the year ending June 2025.

    Source: Exempt Organizations Business Master File, Internal Revenue Service, file dated October 13, 2026.

  5. How long has it been tax-exempt? Passed.

    Recognized by the IRS since March 1977.

    Source: Exempt Organizations Business Master File, Internal Revenue Service, file dated October 13, 2026.

  6. Is it in good standing with state regulators? Passed.

    Not on California's list of charities barred from soliciting. Other states are not yet checked.

    Source: May Not Operate or Solicit for Charitable Purposes list, California Attorney General, Registry of Charities and Fundraisers, file dated October 21, 2026.

Ratings and checks are our reading of public records, using the published method. They are not a statement about anyone's honesty. If you work for this organization, you can send corrections or results, confirm you want gifts through Veridonate, or ask to be removed from giving.