WhCertificate – Overview

WhCertificate is a unified W-9/W-8 collection endpoint that allows your recipients to choose and complete the appropriate form based on their citizenship and tax status. This is the recommended endpoint when your recipient base includes or may include non-U.S. persons, or when you cannot determine in advance which form applies to each recipient.

If your recipient base is exclusively U.S. persons, use the FormW9 endpoint. If it is exclusively non-U.S. individuals, use the FormW8BEN endpoint.

Common use cases

• Gig and freelance platforms — Onboard contractors from both the U.S. and abroad. Each contractor
  self-selects the right form based on their tax status.
• Marketplace and payout platforms — Collect W-9/W-8 from sellers, service providers, or affiliates before issuing payments, regardless of their country of residence.
• Property management software — Gather certificates from domestic and foreign property owners receiving rental income payments.
• Healthcare market research platforms — Collect W-9 or W-8 from physicians and consultants participating in surveys or advisory programs before issuing 1099 or 1042-S payments.

Explore more about use cases

Supported forms

Recipients can choose and complete the appropriate one.

Form	Applies to
W-9	U.S. citizens, resident aliens, and entities
W-8BEN	Non-U.S. individuals
W-8BEN-E	Non-U.S. entities
W-8ECI	Non-U.S. individuals or entities claiming income effectively connected with a U.S. trade or business
W-8IMY	Intermediaries, flow-through entities or certain U.S. branches
W-8EXP	Foreign governments, tax-exempt organizations, foreign central banks of issue, and other specific entities

WhCertificate endpoints

Use the following endpoints to automate W-9/W-8 collection, manage collected forms, and track submission status across your recipient base.

All endpoints require a Bearer token from the OAuth 2.0 authentication flow. Include this token in the Authorization header of every request. Learn more about OAuth 2.0

Collection

Based on the W-9/W-8 collection method you’d like to use, you can call the corresponding endpoint.

Method	How it works	Best for	URL scope
RequestByEmail	TaxBandits sends an email with a unique secure URL to each recipient	Direct outreach to known recipients	Unique per recipient
RequestByText	TaxBandits sends an SMS with a unique secure URL to each recipient	SMS-preferred recipients	Unique per recipient
RequestByUrl	API returns a unique secure URL — you deliver it through your own channel	Embedded portal or onboarding flows	Unique per recipient
RequestByBusinessUrl	API returns a single shared public URL for the payer — you embed it wherever recipients access it	High-volume or self-serve onboarding	Unique per payer. Shared across all recipients
Drop-In UI	A ready-made form interface embedded directly into your platform — no URL generation or delivery required	Platforms that want a fully embedded, brandable experience with no per-recipient API calls	Not applicable — form is rendered inline

Same recipients associated with multiple payers?

If the same payee transacts with multiple payers on your platform, you do not need to request a new W-9/W-8 for each payer. Request once, collect the form, and use the LinkWhCertificate endpoint to attach it to other payers.

Upload Existing Forms

• Create – If you already have the W-9/W-8 form on file, you can upload the form to the TaxBandits API without sending a collection request.

Status Retrieval

• Status – Retrieve the current status of form submission and TIN Matching result (If opted).
• Webhooks – As an alternate to the Status endpoint, you can configure webhooks for the event type ‘WhCertificate Status Change’ to receive automated notifications. Learn more

Other Actions

• Get – Retrieve the details and PDF download link for a submitted W-9/W-8 form.
• List – List all W-9/W-8 certificates associated with a specific payer.
• Delete – Delete a W-9/W-8 certificate for a specific recipient.
• ExpireLink – Deactivate a previously generated secure URL for a payer.

Automate TIN Matching with W-9 collection

TIN Matching validates a recipient’s name and TIN against the IRS database immediately after they submit their W-9. This eliminates the risk of backup withholding, IRS penalties, and incorrect 1099 filings caused by mismatched taxpayer data.

• To trigger TIN Matching automatically when the recipient submits their W-9 form, Set IsTINMatching to TRUE in your API request.
• TIN Matching results are returned in the Status endpoint response or webhooks (if configured).

Customization options​​​

• Branding — Customize the form completion page and the email sent to recipients with your own logo, colors, and styling before deploying W-9/W-8 collection. See how
• Forms displayed — Control which W-9/W-8 forms are presented to recipients on the selection screen. If your platform only works with certain recipient types, you can limit the list to the relevant forms so recipients are never shown options that don't apply to them. See how
• Preferred language — Set the default display language for the form completion page. Supported languages: English, Spanish, French, German, Ukrainian, and Portuguese. Recipients can change their language preference at any time.
• Interview mode — Present the W-9 as a guided step-by-step interview instead of the traditional form layout. Useful for recipients who are less familiar with tax forms.