Upload a document to a session
Upload a document image (ID front, ID back, or selfie) to a session via
the API. This enables document submission from native mobile apps or
custom UIs without using the hosted capture flow.
If a document of the same type already exists, it is replaced (idempotent).
If the session was in `pending` status, it transitions to `capturing`.
**Required scope:** `documents:write`
Authentication
X-API-Keystring
Organization API key. Keys are prefixed with vk_live_ (production) or
vk_sandbox_ (sandbox).
Path parameters
session_id
Session ID (ses_*).
Headers
Verifa-Version
API version date string (e.g. 2026-02-01). If omitted, the version
pinned to your API key is used.
Request
This endpoint expects a multipart form containing a file.
file
The document image file (JPEG, PNG, WebP, or PDF). Max 10MB.
document_type
The type of document being uploaded.
poa_document_type
Proof-of-address document subtype (e.g. utility_bill, bank_statement). Required when document_type is proof_of_address.
poa_document_date
Date on the proof-of-address document (YYYY-MM-DD).
Response
Document uploaded successfully.
id
Public ID of the uploaded document.
session_id
Public ID of the session.
document_type
The type of document uploaded.
mime_type
MIME type of the uploaded file.
file_size_bytes
Size of the uploaded file in bytes.
created_at
When the document was uploaded.
Errors
400
Bad Request Error
401
Unauthorized Error
404
Not Found Error
422
Unprocessable Entity Error