DOCS/FLUX/Vat Filing

Single Filing

Submit a single VAT transaction for processing and filing via the FLUX API. This endpoint is designed for real-time or low-volume VAT submissions where each transaction is filed individually.

Use this when:

You want to file VAT for a single schedule
You do not require batch processing

HTTP Request

POSThttps://api.taxstreem.com/v1/flux/vat-filing/single

Request Body

The following parameters are required for this action.

Parameter	Type	Description
encryptedPayload	string	The encrypted payload of the TaxPromax credentials of the filing user.
filingId	string	Your unique ID for the filing.
month	number	The month you are filing for.
year	number	The year you are filing for.
vatStatus	number	The status of the transaction (e.g., 0-VATABLE, 1-ZERO RATED, 2-VAT EXEMPT).
amount	number	The amount for the item exclusive of VAT.
item	string	The item name e.g. Baby diapers.
narration	string	A description or narration for the item.
taxId	string	The unique Tax Identification Number of the customer, if not provided, just use 0.
beneficiary	string	The name of the customer, if not provided, just use 'retail customer'.

Encrypted Payload (In-Flight Encryption)

FLUX requires sensitive credentials to be encrypted at the application layer before transmission. This provides defense-in-depth on top of HTTPS.

The encryptedPayload field must contain a Base64-encoded AES-256-GCM encrypted JSON object.

Encryption Specification

Property	Value
Algorithm	AES-256-GCM
Key Derivation	SHA-256(sharedSecret)
IV (Nonce)	12 bytes (96-bit) random
Auth Tag	16 bytes (128-bit)
Encoding	Base64

Payload Format

The final transmitted value must be:

Base64( IV[12] || Ciphertext || AuthTag[16] )

IV is randomly generated per request
Ciphertext is encrypted JSON
AuthTag is automatically appended by GCM

Example Request

curl -X POST https://api.taxstreem.com/v1/flux/vat-filing/single \
  -H "x-api-key: txsm_test_SK489c..." \
  -H "Content-Type: application/json" \
  -d {
        "encryptedPayload": 'encrypted_string_...',
        "filingId": '123-abuiod-90',
        "month": 1,
        "year": 2024,
        "data": [
           {
               "vatStatus": 1,
               "amount": 5000,
               "item": "Baby diapers",
               "narration": "Bought kisskid diaper",
               "taxId": "2345544-0001",
               "beneficiary": "Retail Customer"
           }
        ]
     }

Example Response

202 Accepted

{
  "status":  "accepted",
  "message":  "schedule accepted successfully",
  "data":  {
    "id":  "xaee2ddf-effvkfes",
    "created_at":  "2026-02-20T10:00:00Z"
  }
}