Add supporting documents

Last updated: December 24, 2025

Use the Platforms API to add the supporting documents required for:

Completing the due diligence checks for a Full account
Connecting a bank account as part of the Platforms solution

When creating or updating a sub-entity, you can use the API to upload the following document types:

Identity verification documents
Company verification documents
Financial verification documents

You can also use it to upload your bank verification documentation when creating a payment instrument.

To add supporting documentation to a sub-entity, follow these steps:

Generate a file upload link.
Upload the file.
Retrieve the file to verify status.
Attach the file to the sub-entity.

The Platforms API accepts the following types of documents for identity verification. Depending on the document type, you may need to provide both the front and back sides. See the table below to find out more.

Document type	Sides required
Passport	Front only
Driving license	Front and back
National identity card	Front and back
Citizen card	Front and back
Residence permit	Front and back
Electoral ID	Front and back
Bank statement	Front only

Call the Upload a file endpoint, and provide the following fields:

entity_id – The ID of the sub-entity you are uploading the file for.
purpose – The purpose of the document. For example, for an identity verification document, set purpose to identity_verification. For a full list of possible fields, see our API reference.

If the documentation requires both the back and front sides, you must create two different upload links.

Information

Your base URL [prefix] is unique. To learn how to retrieve your unique base URLs for the sandbox and production environments, see API endpoints.

post

https://files.checkout.com/files

Note

Notice that the sub-domain – files.checkout.com – is slightly different to Checkout.com's other endpoints.


1{
2  "entity_id": "ent_5plzb2y4dlqehanhm7i2swsuxc",
3  "purpose": "identity_verification"
4}

A successful response returns:

an upload URL for uploading the file.
an id that represents the file. You will need this id to attach the file to the sub-entity.


1{
2  "id": "file_am2y22gp6wzwqgsyv5h2mldy3y",
3  "document_types_for_purpose": ["image/png", "image/jpg", "image/jpeg"],
4  "maximum_size_in_bytes": "4194304",
5  "_links": {
6    "upload": {
7      "href": "https://s3.eu-west-1.amazonaws.com/mp-files-api-staging-sbox/ent_e5fxiiuec7yasswclx27zbpbcc/file_am2y22gp6wzwqgsyv5h2mldbb6y?AWSAccessKeyId=XX&Expires=1673456742&Signature=fg9Eq3mQBXrlnbeWCTyrURlBxQ%3X"
8    },
9    "self": {
10      "href": "https://files.sandbox.checkout.com/files/file_am2y22gp6wzwqgsyv5h2mldbb6y"
11    }
12  }
13}

Note

Only needed for sub-entities who have been onboarded as a company.


1{
2  "entity_id": "ent_5plzb2y4dlqehanhm7i2swsuxc",
3  "purpose": "company_verification"
4}

A successful response returns:

an upload URL for uploading the file.
an id that represents the file. You will need this id to attach the file to the sub-entity.


1{
2  "id": "file_am2y22gp6wzwqgsyv5h2mldy3y",
3  "document_types_for_purpose": ["image/png", "image/jpg", "image/jpeg", "application/pdf"],
4  "maximum_size_in_bytes": "4194304",
5  "_links": {
6    "upload": {
7      "href": "https://s3.eu-west-1.amazonaws.com/mp-files-api-staging-sbox/ent_e5fxiiuec7yasswclx27zbpbcc/file_am2y22gp6wzwqgsyv5h2mldbb6y?AWSAccessKeyId=XX&Expires=1673456742&Signature=fg9Eq3mQBXrlnbeWCTyrURlBxQ%3X"
8    },
9    "self": {
10      "href": "https://files.sandbox.checkout.com/files/file_am2y22gp6wzwqgsyv5h2mldbb6y"
11    }
12  }
13}


1{
2  "entity_id": "ent_5plzb2y4dlqehanhm7i2swsuxc",
3  "purpose": "bank_verification"
4}

A successful response returns:

an upload URL for uploading the file.
an id that represents the file. You will need this id to attach the file to the sub-entity.


1{
2  "id": "file_am2y22gp6wzwqgsyv5h2mldy3y",
3  "document_types_for_purpose": ["image/png", "image/jpg", "image/jpeg", "application/pdf"],
4  "maximum_size_in_bytes": "4194304",
5  "_links": {
6    "upload": {
7      "href": "https://s3.eu-west-1.amazonaws.com/mp-files-api-staging-sbox/ent_e5fxiiuec7yasswclx27zbpbcc/file_am2y22gp6wzwqgsyv5h2mldbb6y?AWSAccessKeyId=XX&Expires=1673456742&Signature=fg9Eq3mQBXrlnbeWCTyrURlBxQ%3X"
8    },
9    "self": {
10      "href": "https://files.sandbox.checkout.com/files/file_am2y22gp6wzwqgsyv5h2mldbb6y"
11    }
12  }
13}


1{
2  "entity_id": "ent_5plzb2y4dlqehanhm7i2swsuxc",
3  "purpose": "financial_verification"
4}

A successful response returns:

an upload URL for uploading the file.
an id that represents the file. You will need this id to attach the file to the sub-entity.


1{
2  "id": "file_am2y22gp6wzwqgsyv5h2mldy3y",
3  "document_types_for_purpose": ["image/png", "image/jpg", "image/jpeg", "application/pdf"],
4  "maximum_size_in_bytes": "4194304",
5  "_links": {
6    "upload": {
7      "href": "https://s3.eu-west-1.amazonaws.com/mp-files-api-staging-sbox/ent_e5fxiiuec7yasswclx27zbpbcc/file_am2y22gp6wzwqgsyv5h2mldbb6y?AWSAccessKeyId=XX&Expires=1673456742&Signature=fg9Eq3mQBXrlnbeWCTyrURlBxQ%3X"
8    },
9    "self": {
10      "href": "https://files.sandbox.checkout.com/files/file_am2y22gp6wzwqgsyv5h2mldbb6y"
11    }
12  }
13}

Before uploading a file, make sure the following requirements are met:

The uploaded file must be no larger than 4MB.
For identity verification documents, the file must be in either JPEG, JPG, or PNG format.
For bank statements, company verification, and financial verification documents, the file must be in either JPEG, JPG, PNG, or PDF format.
If you are uploading a bank statement to verify a set of bank details, you have configured your webhook server and subscribed to the payment_instrument_verification_passed and payment_instrument_verification_failed webhooks.

To upload a file, send a data-binary type request to the upload URL you received in the previous step, with the file attached.


1curl --location --request PUT "https://s3.eu-west-1.amazonaws.com/mp-files-api-staging-sbox/ent_e5fxiiuec7yasswclx27zbpbcc/file_am2y22gp6wzwqgsyv5h2mldbb6y?AWSAccessKeyId=XX&Expires=1673456742&Signature=fg9Eq3mQBXrlnbeWCTyrURlBxQ%3X"
2--data-binary '@/C:/Users/Test/test.pdf'

A successful response returns a 200 HTTP response code, indicating the file has been uploaded.

You can retrieve information about a previously uploaded file and check its status.

A file can have one of the following statuses:

Verified – The file is ready to be used in an onboarding request.
Pending – The file is pending verification or virus scanning.
Invalid – See the status_reasons property for more information:
- invalid_mime_type– The mime type does not match the allowed content types for the specified document purpose – for example, a PDF document was uploaded for identity verification.
- file_size_limit_exceeded– The file is larger than 4MB.
Failed verification – The file is malicious.

To retrieve information about a previously uploaded file, call the Retrieve a file endpoint. Include the id of the file returned when you generated the file upload link in your request.

For example, https://files.checkout.com/files/file_am2y22gp6wzwqgsyv5h2mldy3y.

Information

Your base URL [prefix] is unique. To learn how to retrieve your unique base URLs for the sandbox and production environments, see API endpoints.

get

https://files.checkout.com/files/{file_id}


1{
2  "id": "file_bgwa24ijrknm6a3zlqydctnkou",
3  "mime_type": "image/jpeg",
4  "purpose": "identity_verification",
5  "size": 7111,
6  "status": "verified",
7  "uploaded_on": "2023-01-16T11:07:04.497Z",
8  "_links": {
9    "download": {
10      "href": "https://files.sandbox.checkout.com/files/ent_e5fxiiuec7yasswclx27zbpbcc/file_bbmcujt2fxmyh5pmeuz2bvvxd?AWSAccessKeyId=XX&Expires=1673456742&Signature=fg9Eq3mQBXrlnbeWCTyrURlBxQ%3X"
11    },
12    "self": {
13      "href": "https://files.sandbox.checkout.com/files/file_bbmcujt2fxmyh5pmeuz2bvvxd"
14    }
15  }
16}


1{
2  "id": "file_a4q47zqvlgwdbladiuxrdjxxx",
3  "mime_type": "application/pdf",
4  "purpose": "identity_verification",
5  "size": 25692,
6  "status": "invalid",
7  "status_reasons": ["invalid_mime_type"],
8  "uploaded_on": "2023-01-16T11:01:32.226Z",
9  "_links": {
10    "self": {
11      "href": "https://files.sandbox.checkout.com/files/file_a4q47zqvlgwdbladiuxrdjxxx"
12    }
13  }
14}

You can attach a file to a sub-entity when you onboard a sub-entity, or update a sub-entity.

To attach an identity verification document to a sub-entity, include the identification.document object in your onboarding or update request, with the following information:

type – The type of identification document provided. See accepted document types.
front – The id returned when you uploaded the front side of the document. This is required for all identification types.
back – The id returned when you uploaded the back side of the document. This is only required if the type is not a passport or a bank statement.


1{
2  "individual": {
3    "first_name": "Daniel",
4    "last_name": "Yubi",
5    "trading_name": "Daniel's Donuts",
6    "national_tax_id": "1234567",
7    "registered_address": {
8      "address_line1": "90 Tottenham Court Road",
9      "city": "London",
10      "zip": "W1T4TJ",
11      "country": "GB"
12    },
13    "date_of_birth": {
14      "day": 5,
15      "month": 6,
16      "year": 1995
17    },
18    "identification": {
19      "document": {
20        "type": "passport",
21        "front": "file_jxaps37jnfaupfu6bsei7rj5iu"
22      }
23    }
24  }
25}


1{
2  "representatives": [
3    {
4      "first_name": "Chrisi",
5      "last_name": "Webster",
6      "address": {
7        "address_line1": "123 ABC Close",
8        "city": "London",
9        "zip": "E1 5DP",
10        "country": "GB"
11      },
12      "date_of_birth": {
13        "day": 5,
14        "month": 6,
15        "year": 1995
16      },
17      "identification": {
18        "document": {
19          "type": "passport",
20          "front": "file_jxaps37jnfaupfu6bsei7rj5iu"
21        }
22      }
23    }
24  ]
25}

Note

Providing an identity document is the last step before triggering due diligence checks. To prevent multiple due diligence checks, add all representatives before uploading their identification documents.

Note

Company verification documents are only needed for sub-entities who are onboarded as a company.

To attach a company verification document to a sub-entity, include the company.document object in your onboarding or update request, with the following information:

file_id – The id returned when you uploaded the file.
type – The type of document you are providing. For example, a certificate of incorporation.


1{
2  "company": {
3    "business_registration_number": "452349600005",
4    "legal_name": "The Cake Shop Inc.",
5    "trading_name": "The Cake Shop",
6    "principal_address": {
7      "address_line1": "90 Tottenham Court Road",
8      "city": "London",
9      "zip": "W1T4TJ",
10      "country": "GB"
11    },
12    "document": {
13      "file_id": "file_6lbss42ezvoufcb2beo76rvwly",
14      "type": "Certificate of incorporation"
15    }
16  }
17}

Verification requirements

Learn about the information required for sub-entity verification.

Add supporting documents

Identity document types and requirements

Generate a file upload link

Information

Note

Request examples

Response example

Note

Response example

Response example

Response example

Upload a file

Request example

Retrieve a file

Information

Response examples

Attach a file to the sub-entity

Identification documents

Note

Company verification documents

Note

Related topics

Verification requirements