Exemption Certificate Management

Exemption Certificate Management (ECM) gives sellers a structured way to collect, store, and apply US sales tax exemption certificates — and to demonstrate compliance when audited. Under US sales tax law, a seller who fails to collect tax must prove it holds a valid, unexpired exemption certificate for that buyer and jurisdiction. Without documented certificates, the seller bears the tax liability.

Key capabilities

• Structured certificate storage — capture certificate number, jurisdiction, form type, buyer details, and validity dates in a single record per certificate
• Calculation integration — reference a stored certificate at calculation time using customer.exemptionRef to zero-rate the transaction automatically
• Buyer collection wizard — generate a hosted link that guides a buyer through completing and submitting their exemption form; no custom UI required
• Automated expiry alerts — renewal reminders sent at 60, 30, 14, and 7 days before a certificate expires
• Audit readiness score — a 0–100 score across your certificate portfolio, updated in real time as certificates are added, expire, or are renewed
• Gap analysis — identifies buyers with taxable purchases in a jurisdiction where no valid certificate is on file
• SST multi-state certificates — a single Streamlined Sales Tax certificate can cover all 24 SST member states

Create a Certificate

Creates a new exemption certificate record. The record stores the certificate metadata — jurisdiction, form type, validity dates, and your own reference — alongside the buyer's details. It does not store the underlying document file; attach the scanned certificate to your document management system and reference it via certificateRef.

Endpoint

POST https://api.clearvo.io/v1/tax/exemptions

curl https://api.clearvo.io/v1/tax/exemptions \
  -X POST \
  -H "x-api-key: csk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "certificateRef": "CERT-TX-ACME-2026-001",
    "customerRef": "cus_abc123",
    "customerName": "Acme Manufacturing LLC",
    "buyerTaxId": "12-3456789",
    "certificateType": "MANUFACTURING",
    "country": "US",
    "region": "TX",
    "effectiveFrom": "2026-01-01",
    "effectiveTo": "2026-12-31"
  }'

{
  "id": "cl_cert_01j9...",
  "ids": ["cl_cert_01j9..."],
  "certificateRef": "CERT-TX-ACME-2026-001",
  "customerRef": "cus_abc123",
  "customerName": "Acme Manufacturing LLC",
  "buyerTaxId": "12-3456789",
  "certificateType": "MANUFACTURING",
  "country": "US",
  "regions": ["TX"],
  "regionNames": ["Texas"],
  "effectiveFrom": "2026-01-01",
  "effectiveTo": "2026-12-31",
  "status": "ACTIVE",
  "createdAt": "2026-06-26T10:00:00.000Z"
}

Request fields

Certificate status values

Other certificate endpoints

Apply a Certificate at Calculation

To apply a stored exemption certificate to a transaction, pass customer.exemptionRef in the POST /v1/tax/calculate request body. Clearvo looks up the certificate, verifies it is ACTIVE and covers the transaction's jurisdiction, and applies a zero rate with tax code E (exempt) to qualifying line items.

This approach keeps the exemption decision in the API layer — your billing or ERP system passes the certificate ID it already holds for the buyer, and Clearvo resolves whether the exemption is valid for the current transaction.

curl https://api.clearvo.io/v1/tax/calculate \
  -X POST \
  -H "x-api-key: csk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "currency": "USD",
    "commit": true,
    "seller": {
      "country": "US",
      "address": { "country": "US", "region": "TX" }
    },
    "customer": {
      "exemptionRef": "ecm_01j9...",
      "address": { "country": "US", "region": "TX" }
    },
    "lineItems": [
      {
        "id": "line-1",
        "amount": 4500.00,
        "productName": "Industrial conveyor components"
      }
    ]
  }'

{
  "calculationId": "cl_calc_02k7...",
  "committed": true,
  "currency": "USD",
  "exemption": {
    "id": "ecm_01j9...",
    "applied": true,
    "status": "ACTIVE",
    "certificateRef": "CERT-TX-ACME-2026-001"
  },
  "lineItems": [
    {
      "id": "line-1",
      "taxCode": "E",
      "rate": 0,
      "taxableAmount": 4500.00,
      "taxAmount": 0,
      "totalAmount": 4500.00
    }
  ],
  "totals": {
    "subtotal": 4500.00,
    "totalTax": 0,
    "total": 4500.00
  }
}

The response includes an exemption object confirming which certificate was applied and its current status at the time of the calculation. If the certificate is EXPIRED or REVOKED at calculation time, the field exemption.applied is false, the standard tax rate is applied, and the response includes an exemption.reason string explaining why the certificate was not used.

Buyer Collection Wizard

The buyer wizard provides a hosted, guided flow where the buyer completes and submits their exemption certificate. You generate a time-limited collection link via the API and send it to the buyer — by email, embedded in your portal, or included on an invoice. When the buyer completes the form, the certificate record is created in your account automatically and a webhook event is fired.

This eliminates the need to build a custom exemption collection UI and reduces certificate rejection rates caused by incorrectly completed forms — the wizard enforces the required fields for the selected form type and jurisdiction.

Generate a collection link

POST https://api.clearvo.io/v1/tax/exemptions/{id}/collection-link

Where {id} is an existing certificate record ID. If you do not yet have a certificate record for the buyer, create a stub record first (with validFrom and jurisdiction populated but no validTo or certificateRef) and then generate the link against that record.

curl https://api.clearvo.io/v1/tax/exemptions/ecm_01j9.../collection-link \
  -X POST \
  -H "x-api-key: csk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "expiresIn": 604800,
    "redirectUrl": "https://yourapp.com/onboarding/complete"
  }'

{
  "url": "https://app.clearvo.io/collect/tok_abc123xyz",
  "token": "tok_abc123xyz",
  "expiresAt": "2026-07-03T10:00:00.000Z"
}

Send the url to the buyer. The wizard at app.clearvo.io/collect/{token} is pre-populated with the jurisdiction, form type, and buyer name from the certificate record. The buyer fills in their details, signs, and submits. On submission:

• The certificate record is updated with the submitted data and its status changes to ACTIVE
• A certificate.collected webhook event is sent to your configured endpoint
• The buyer is redirected to the redirectUrl you specified, if provided

Collection link fields

Expiry Tracking and Renewal Alerts

For any certificate with a validTo date set, Clearvo sends automated renewal alerts before expiry. Alerts are delivered as webhook events and as email notifications to the account's configured email address.

Alert schedule

Webhook payload

All certificate lifecycle events share the same payload shape:

{
  "event": "certificate.expiry_warning",
  "data": {
    "id": "ecm_01j9...",
    "buyerName": "Acme Manufacturing LLC",
    "buyerTaxId": "12-3456789",
    "region": "TX",
    "certificateRef": "CERT-TX-ACME-2026-001",
    "validTo": "2026-12-31",
    "daysUntilExpiry": 30
  },
  "createdAt": "2026-12-01T00:00:00.000Z"
}

To receive webhook events, configure your endpoint in the Clearvo dashboard under Settings > Webhooks, or via the Webhooks API. Subscribe to the certificate.* event category to receive all certificate lifecycle events.

Audit Readiness Score

The audit readiness score is a 0–100 integer that reflects the health of your exemption certificate portfolio at a point in time. It is computed across all exempt transactions for your entity and accounts for missing certificates, expired certificates, and certificates nearing expiry. A score of 100 means every exempt sale can be substantiated with a valid, current certificate. A score below 80 indicates material audit risk.

Endpoint

GET https://api.clearvo.io/api/tenant/exemptions/audit-score

curl https://api.clearvo.io/api/tenant/exemptions/audit-score \
  -H "x-api-key: csk_live_..."

{
  "score": 84,
  "totalExemptTransactions": 312,
  "coveredTransactions": 262,
  "uncoveredTransactions": 50,
  "activeCertificates": 41,
  "expiringWithin30Days": 6,
  "expiredCertificates": 3,
  "gaps": 9,
  "calculatedAt": "2026-06-26T10:00:00.000Z"
}

Response fields

Gap Analysis

The gap analysis endpoint identifies every buyer-jurisdiction pair where your entity has made exempt sales but does not hold a valid, active certificate. Each gap represents a potential audit finding — the tax authority may assess the uncollected tax plus interest and penalties if you cannot produce a certificate to justify the exemption.

Endpoint

GET https://api.clearvo.io/api/tenant/exemptions/gaps

curl "https://api.clearvo.io/api/tenant/exemptions/gaps?page=1&limit=50" \
  -H "x-api-key: csk_live_..."

{
  "gaps": [
    {
      "buyerName": "Delta Supplies Inc",
      "buyerTaxId": "98-7654321",
      "country": "US",
      "region": "CA",
      "exemptTransactionCount": 14,
      "exemptSalesTotal": 28340.00,
      "currency": "USD",
      "estimatedTaxExposure": 2919.02,
      "oldestExemptSaleDate": "2026-01-08",
      "latestExemptSaleDate": "2026-06-22"
    }
  ],
  "total": 9,
  "page": 1,
  "limit": 50
}

Response fields

SST Multi-State Certificates

The Streamlined Sales Tax (SST) programme allows a buyer to submit a single exemption certificate that is valid in all 24 SST member states. Instead of collecting a separate certificate per state, you collect one SST certificate and it covers all member state jurisdictions automatically.

To create an SST certificate, set formType: "SST" and omit the region field. Clearvo stores the certificate as a multi-state record and matches it against transactions in any of the 24 member states when customer.exemptionRef is passed at calculation time.

SST member states

The 24 SST member states as of 2026:

AR, GA, IN, IA, KS, KY, MI, MN, NE, NV, NJ, NC, ND, OH, OK, RI, SD, TN, UT, VT, WA, WV, WI, WY

curl https://api.clearvo.io/v1/tax/exemptions \
  -X POST \
  -H "x-api-key: csk_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "buyerName": "Horizon Wholesale Corp",
    "buyerTaxId": "55-1234567",
    "country": "US",
    "formType": "SST",
    "reason": "Resale — SST multi-state certificate",
    "certificateRef": "CERT-SST-HORIZON-2026",
    "validFrom": "2026-01-01",
    "validTo": "2026-12-31"
  }'

{
  "id": "ecm_02k8...",
  "buyerName": "Horizon Wholesale Corp",
  "buyerTaxId": "55-1234567",
  "country": "US",
  "region": null,
  "formType": "SST",
  "sstMemberStates": ["AR","GA","IN","IA","KS","KY","MI","MN","NE","NV","NJ","NC","ND","OH","OK","RI","SD","TN","UT","VT","WA","WV","WI","WY"],
  "reason": "Resale — SST multi-state certificate",
  "certificateRef": "CERT-SST-HORIZON-2026",
  "validFrom": "2026-01-01",
  "validTo": "2026-12-31",
  "status": "ACTIVE",
  "createdAt": "2026-06-26T10:00:00.000Z"
}

The response includes a sstMemberStates array listing the states covered at the time of creation. When a calculation references this certificate via customer.exemptionRef and the transaction's region matches any member state, the exemption is applied. Non-member states are unaffected — a transaction in CA (California, not an SST member) would not receive the exemption.

Non-SST states

For buyers who also need coverage in non-member states (such as California, New York, or Texas), collect a separate state-specific certificate for each and create individual certificate records with the region field set accordingly. Both the SST certificate and the state-specific certificates can be active for the same buyer simultaneously — Clearvo applies whichever certificate covers the transaction's jurisdiction.