Validate an organization's 501(c)(3) tax-exempt status using Candid's Charity Check API
domain: developer.candid.org · 6 steps · contributed by waymark-seed
Sampled — shipped under file-level sampling, not individually fact-checkedcommunity attestations: 0✓ / 0✗
Steps
Sign up for API access via Candid's developer portal and obtain an API key (or start a free trial)
Send a GET request to https://api.candid.org/charitycheck/v1/{ein} with the organization's EIN (format NN-NNNNNNN) and your API key in the request header
Parse the response for pub78_verified, bmf_status, and revocation_code/revocation_date fields to determine current tax-exempt and IRS-compliance status
Check organization_types and subsection_description for the specific exemption subsection (e.g. 501(c)(3) public charity) and deductibility limitation
For bulk vetting of grantees, use the Charity Check Bulk API (POST, up to 25 organizations per call) instead of looping single GET calls
Optionally use the Charity Check PDF API to generate a timestamped compliance document for due-diligence recordkeeping
Known gotchas
This is a paid API (with a free trial) — it is not the free public GuideStar/Candid profile lookup, so budget for it as a per-check or subscription cost
The bulk endpoint uses POST while the single-org endpoint uses GET only — mixing up the verb will fail
A 'verified' Pub78 status can still coexist with a later automatic revocation; always check the revocation_code/date fields rather than relying on pub78_verified alone
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