> For the complete documentation index, see [llms.txt](https://bellingcat.gitbook.io/toolkit/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://bellingcat.gitbook.io/toolkit/more/all-tools/527-explorer.md).
# 527 Explorer
## URL
## Description
ProPublica's 527 Explorer allows people to review the finances of nonprofit organizations known as 527s in the US. 527s file reports with the Internal Revenue Service (IRS), but these filings appear in a section separate from most nonprofits on the IRS website. ProPublica's database is intended to make searching these filings easier by including tools to help match names, addresses and other information that may have spelling variations. The tool also shows similar contributions and expenditures, allowing the user to possibly uncover other connections between organizations. The database also has a feature which shows which 527s have similar donors and expenditures.
## Cost
* [x] Free
* [ ] Partially Free
* [ ] Paid
## Level of difficulty
## Requirements
Internet access is required for the tool.
## Limitations
The tool is likely best used together with other databases that look at other types of financial contributions and expenditures (Federal Elections Commission, state and local level government websites, lobbying disclosure databases, the Securities and Exchange Commission's EDGAR database, etc.). If a user wishes to view the original IRS form, they may need to visit the IRS website. While the tool has a feature that shows similar donors, a user may also need to be aware of acronyms or name variations of the organizations of interest.
## Ethical Considerations
None
## Guides and articles
ProPublica: [527 Explorer](https://projects.propublica.org/527-explorer/)
ProPublica: [How to Use ProPublica's 527 Explorer](https://www.youtube.com/watch?v=AOeMZUjVxtU), Youtube, July 2024.
Ellis Simani: [How a Network of Nonprofits Enriches Fundraisers While Spending Almost Nothing on Its Stated Cau](https://www.propublica.org/article/political-nonprofits-fundraising-ftc-irs-527s-pacs?)[se](https://www.propublica.org/article/political-nonprofits-fundraising-ftc-irs-527s-pacs?), ProPublica, June 18, 2024.
OpenSecrets: [527 Basics](https://www.opensecrets.org/527s/basics.php)
## Tool provider
[ProPublica](https://www.propublica.org/about/), US.
## Advertising Trackers
* [x] This tool has not been checked for advertising trackers yet.
* [ ] This tool uses tracking cookies. Use with caution.
* [ ] This tool does not appear to use tracking cookies.
| Page maintainer |
| ------------------------- |
| Bellingcat Volunteer Team |
| |
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