Does GDPR or HIPAA apply to accounts payable data?

Much of it is. Vendor contacts, sole traders (whose business and personal identity merge), and employee approvers are identifiable individuals, so their data falls under GDPR. On deletion ("right to erasure") requests, the key principle is that erasure is not absolute: where you have a legal obligation to retain the record - tax, accounting, audit - that obligation generally overrides the deletion request for the data needed to meet it. The correct response is usually to retain the legally-required transaction data, delete or restrict anything not needed for that purpose (marketing contact details, superfluous personal notes), and document the lawful basis for what you keep. Don't delete an invoice you're required to retain for tax just because the vendor asked.

HIPAA enters the picture only when invoices or attachments actually contain protected health information (PHI) - for example, a healthcare provider's invoices that reference identifiable patients. Most AP data isn't PHI, but where it is, the AP system and any vendor processing it become subject to HIPAA's safeguards, and you need a Business Associate Agreement (BAA) with any vendor that handles that PHI on your behalf. The cleaner control, where feasible, is to keep PHI out of the AP workflow entirely - redact or restrict it before invoices enter approval - so the privacy exposure never reaches the people routing the invoice.

Retain what the legal obligation (tax, audit) requires and refuse erasure of that data on the basis of the legal-obligation/legal-claims exemptions; delete or restrict personal data not needed for that purpose; and document your reasoning. Communicate to the requester what you're retaining and why - transparency is itself an obligation.

Employee approvers and users (names, roles, actions), vendor contacts, sole proprietors and individual contractors (whose data is inherently personal), and sensitive financial identifiers - vendor bank account details and tax IDs (TIN/SSN for sole traders). The banking and tax-ID fields are the highest-sensitivity data and warrant the tightest access.

On least privilege: only roles that genuinely need to view or edit banking and tax data should have it, ideally with additional authentication for exports of that data, and with all access and changes logged. Most AP users never need to see a full bank account number; scope visibility accordingly.

If the vendor processes PHI on your behalf through the AP system, yes - a BAA is required to use them compliantly under HIPAA. If you keep PHI out of the AP workflow, the BAA need may not arise; confirm with counsel based on what actually flows through the system.

It can. GDPR restricts transfers of EU personal data outside adequate jurisdictions, so where your AP vendor hosts and processes EU supplier and contact data matters for compliance and may require specific transfer mechanisms in your data processing agreement. Raise hosting region and transfer safeguards in vendor due diligence.

Sometimes, though many state laws exempt much B2B data and have thresholds based on company size and data volume. Sole-trader and individual-contact data can fall in scope; pure company-to-company invoice data often doesn't. Assess against the specific state law's scope and exemptions rather than assuming AP is exempt.

Document what personal data the AP system processes, the lawful basis, who has access, retention periods, where it's hosted, and any third-party processors (with their agreements). The AP system belongs in your record of processing activities because it holds vendor and employee personal data and sensitive financial identifiers.

Best handled upstream and by policy: define who is responsible for screening incoming documents, redact PHI/PII not needed for processing before the invoice enters routing, and restrict access to any sensitive fields that must remain. Keeping sensitive data out of broad approval visibility is easier and safer than tightly controlling it after it's everywhere.

Stampli supports the access and accountability controls these regimes require. Role-based permissions restrict who can see and act on sensitive fields, and access to vendor tax information exports is protected by MFA. For HIPAA-enabled accounts, Stampli supports document-access accountability for sensitive invoice records, available under the appropriate legal and configuration process including a BAA - a compliance-support capability maintained for regulated use cases rather than a standard outward-facing feature. Stampli's compliance posture supports privacy-sensitive and regulated environments; HIPAA and GDPR obligations are met through that access control, accountability, and agreement framework rather than any single setting.