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Before you start

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 This quickstart guide walks you through registering a user, uploading documents, and fetching document details using Crossmint’s APIs. These steps enable your users to access regulated products like onramp, offramp, and payouts.
The user KYC API must be enabled for your project. If calls return "project not configured to support the users KYC endpoints", contact sales to enable it.
User locators use the userId: format, a unique identifier you choose for the user, for example userId:johnd-123.
1

User accepts Crossmint's Privacy Policy

Before sharing any user KYC data with Crossmint, you must ensure your users have accepted Crossmint’s Privacy Policy. This is a prerequisite for companies sharing their customer’s KYC data with Crossmint.
Once the user has accepted the privacy policy, record their acceptance using the following API call:
curl --request PUT \
    --url 'https://staging.crossmint.com/api/2025-06-09/users/userId:johnd-123/legal-documents' \
    --header 'X-API-KEY: <your-server-api-key>' \
    --header 'Content-Type: application/json' \
    --data '{
        "type": "crossmint-privacy-policy",
        "acceptedAt": "2025-10-05T14:48:00Z"
    }'
This call also creates a user with the specified userLocator if one does not already exist.
2

Register user information

Register a user with Crossmint by specifying their userLocator, their personal details, and KYC data using the Create User endpoint
curl --request PUT \
    --url 'https://staging.crossmint.com/api/2025-06-09/users/userId:johnd-123' \
    --header 'X-API-KEY: <your-server-api-key>' \
    --header 'Content-Type: application/json' \
    --data '{
        "userDetails": {
            "firstName": "John",
            "lastName": "Doe",
            "dateOfBirth": "1995-01-01",
            "countryOfResidence": "DE"
        }
    }'
3

Run identity verification

Once you have registered relevant user information you can trigger checks via the Trigger Identity Verification endpoint.
curl --request PUT \
    --url 'https://staging.crossmint.com/api/2025-06-09/users/userId:johnd-123/identity-verification' \
    --header 'X-API-KEY: <your-server-api-key>'
The response will include the eligibility status for each verification type (regulated-transfer, onramp, onramp-light, offramp):
  • not-started: Verification has not been initiated
  • pending-privacy-policy: User has not yet accepted Crossmint’s Privacy Policy
  • requires-data: Additional user data or documents are needed
  • pending-review: Verification is in progress
  • pending-manual-review: Verification requires manual review by Crossmint’s compliance team
  • verified: User has passed verification
  • rejected: User has failed verification
Once a product reads verified, the user can use it. A verified offramp status, for example, means the user can cash out through Offramp.If any of them return requires-data, you must aggregate the missingData and missingDocuments arrays from those specific eligibility objects. Then, update the user’s information using the Update User endpoint and/or upload additional documents using the Upload Document endpoint, and finally re-trigger the verification.
{
    "eligibility": [
        {
            "type": "regulated-transfer",
            "status": "pending-review" // or "verified"
        },
        {
            "type": "onramp",
            "status": "requires-data",
            "missingData": ["kyc-data", "due-diligence", "verification-history"],
            "missingDocuments": ["id", "selfie-front"] // "proof-of-address" and "proof-of-income" may also be requested in case of Enhanced Due Diligence 
        },
        {
            "type": "onramp-light",
            "status": "requires-data",
            "missingData": ["kyc-data"] // light KYC requires less data and no document uploads
        },
        {
            "type": "offramp",
            "status": "requires-data",
            "missingData": ["kyc-data", "due-diligence", "verification-history"],
            "missingDocuments": ["id", "selfie-front"] // "proof-of-address" and "proof-of-income" may also be requested in case of Enhanced Due Diligence 
        }
    ]
}
4

Update user information

Register additional user information with Crossmint so the user can access onramp and offramp services.
Calling this endpoint again with the same userLocator will update the existing user’s information. The endpoint is not additive so specify all relevant user information when updating the user.
curl --request PUT \
    --url 'https://staging.crossmint.com/api/2025-06-09/users/userId:johnd-123' \
    --header 'X-API-KEY: <your-server-api-key>' \
    --header 'Content-Type: application/json' \
    --data '{
        "userDetails": {
            "firstName": "John",
            "lastName": "Doe",
            "dateOfBirth": "1995-01-01",
            "countryOfResidence": "DE"
        },
        "kycData": {
            "nationality": "DE",
            "addressOfResidence": {
                "line1": "123 Hauptstrasse",
                "line2": "Apt 5",
                "city": "Berlin",
                "stateOrRegion": "Berlin",
                "postalCode": "10115"
            },
            "email": "johnd@example.com",
            "identityDocument": {
                "type": "passport",
                "number": "AS12321",
                "issuingCountryCode": "DE"
            }
        },
        "dueDiligence": {
            "employmentStatus": "full-time",
            "sourceOfFunds": "salary-disbursement",
            "industry": "financial-institution"
        },
        "verificationHistory": {
            "idVerificationTimestamp": "2024-01-15T10:30:00Z",
            "livenessVerificationTimestamp": "2024-01-15T10:32:00Z"
        }
    }'
5

Upload a document

Upload identity or supporting documents for the user using the Upload Document endpoint. Documents are associated with the user via their userLocator.
curl --request POST \
    --url 'https://staging.crossmint.com/api/2025-06-09/documents' \
    --header 'X-API-KEY: <your-server-api-key>' \
    --header 'Content-Type: application/json' \
    --data '{
        "reference": {
            "userLocator": "userId:johnd-123"
        },
        "documentType": "id-passport",
        "data": "<base64-encoded-image>",
        "expiresAt": "2030-12-31"
    }'
Supported document types:
  • Identity documents: id-passport, id-idcard-front, id-idcard-back, id-residency-permit (Spain residents only)
  • Supporting documents: proof-of-address, proof-of-income
  • Selfie documents: selfie-front, selfie-left, selfie-right
US residents provide their identity via SSN in kycData.identityDocument. No identity document upload or selfie is needed for standard on/offramp. However, if Enhanced Due Diligence (EDD) is triggered, US users must also upload a passport (id-passport) or driver’s license (id-idcard-front, id-idcard-back). Proof of income is not required for US EDD users.
Calling this endpoint again with the same userLocator and documentType will update the existing document’s registered information.
6

Run identity verification

Once you have registered the user’s information and uploaded the required documents, trigger the KYC verification process using the Trigger Identity Verification endpoint.
curl --request PUT \
    --url 'https://staging.crossmint.com/api/2025-06-09/users/userId:johnd-123/identity-verification' \
    --header 'X-API-KEY: <your-server-api-key>'
The response will include the eligibility status for each verification type (regulated-transfer, onramp, onramp-light, offramp):
{
    "eligibility": [
        {
            "type": "regulated-transfer",
            "status": "verified"
        },
        {
            "type": "onramp",
            "status": "pending-review"
        },
        {
            "type": "onramp-light",
            "status": "pending-review"
        },
        {
            "type": "offramp",
            "status": "pending-review"
        }
    ]
}
7

Check verification status

Verification runs asynchronously. After triggering it, poll the Get Identity Verification Status endpoint until the relevant product status reads verified. It usually completes within a minute, and the transient state may be not-started or pending-review.
curl --request GET \
    --url 'https://staging.crossmint.com/api/2025-06-09/users/userId:johnd-123/identity-verification' \
    --header 'X-API-KEY: <your-server-api-key>'
8

Fetch user information

You can fetch a user’s information at any time to see their current status, including when they last accepted valid legal documents. Use the Get User endpoint to retrieve this information:
curl --request GET \
    --url 'https://staging.crossmint.com/api/2025-06-09/users/userId:johnd-123' \
    --header 'X-API-KEY: <your-server-api-key>'
The response includes the legalDocuments array, which shows the status of legal document acceptances:
{
    "email": "john.doe@example.com",
    "phoneNumber": "+1234567890",
    "userId": "usr_1234567890",
    "userDetails": true,
    "kycData": false,
    "dueDiligence": false,
    "verificationHistory": false,
    "legalDocuments": [
        {
            "type": "crossmint-privacy-policy",
            "acceptedAt": "2024-01-15T10:30:00Z",
            "validVersion": true
        }
    ]
}
The validVersion field indicates whether the user has accepted the current version of the legal document. If validVersion is false, you should prompt the user to accept the updated terms.

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Launching in Production

For production, the steps are almost identical, but some changes are required:
  1. Create a developer account on the production console
  2. Create a production server API key on the API Keys page with the API scopes users.create, users.read
  3. Replace your test API key with the production key
  4. Replace staging.crossmint.com with www.crossmint.com in the API URLs

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