---
title: "Send ONE from account to account"
method: POST
path: "/v3/one/transaction"
tags: ["Harmony - Tatum API"]
---

# Send ONE from account to account

`POST /v3/one/transaction`

## Request

- Base URL: `https://api.tatum.io`
- URL: `https://api.tatum.io/v3/one/transaction`
- Auth: API key in header `x-api-key`

/v3/one/transaction

**2 credits per API call**

Send ONE from account to account.

The default shard `0` is used for the sender and the recipient.

**Signing a transaction**  
When sending ONE, you are charged a fee for the transaction, and you must sign the transaction with the private key of the blockchain address from which the fee will be deducted.

Providing the private key in the API is not a secure way of signing transactions, because the private key can be stolen or exposed. Your private keys should never leave your security perimeter. You should use the private keys only for testing a solution you are building on the **testnet** of a blockchain.

For signing transactions on the **mainnet**, we strongly recommend that you use the Tatum [Key Management System (KMS)](https://github.com/tatumio/tatum-kms) and provide the signature ID instead of the private key in the API. Alternatively, you can use the [Tatum JavaScript client](https://github.com/tatumio/tatum-js/tree/v2).

Alternatively, using the Tatum client library for supported languages.

## Query parameters

- `shardID` number

## Request body

- union
  - TransferOneBlockchain
    - `amount` string, required: The amount to transfer
    - `currency` 'ONE', required: The currency of the amount to transfer
    - `to` string, required: The blockchain address to transfer the amount to
    - `fromPrivateKey` string, required: The private key of the blockchain address from which the fee will be deducted
    - `fee` CustomFee: The custom defined fee; if not present, will be calculated automatically
      - `gasPrice` string, required: The price for one gas unit (in Gwei)
      - `gasLimit` string, required: The maximum number of gas units that you are willing to spend on processing the transaction at the provided gas price
    - `data` string: Additional data that can be passed to a blockchain transaction as a data property; must be in the hexadecimal format
    - `nonce` number: The nonce to be set to the transaction; if not present, the last known nonce will be used
  - TransferOneBlockchainKMS
    - `amount` string, required: The amount to transfer
    - `currency` 'ONE', required: The currency of the amount to transfer
    - `to` string, required: The blockchain address to transfer the amount to
    - `signatureId` string, uuid, required: The KMS identifier of the private key of the blockchain address from which the fee will be deducted
    - `index` number: (Only if the signature ID is mnemonic-based) The index of the address from which the fee will be deducted that was generated from the mnemonic
    - `fee` CustomFee: The custom defined fee; if not present, will be calculated automatically
      - `gasPrice` string, required: The price for one gas unit (in Gwei)
      - `gasLimit` string, required: The maximum number of gas units that you are willing to spend on processing the transaction at the provided gas price
    - `data` string: Additional data that can be passed to a blockchain transaction as a data property; must be in the hexadecimal format
    - `nonce` number: The nonce to be set to the transaction; if not present, the last known nonce will be used

## Response `200`

OK

- union
  - TransactionHash
    - `txId` string, required: The hash (ID) of the transaction
  - SignatureId
    - `signatureId` string, uuid, required: The internal Tatum ID of the prepared transaction for Key Management Sysytem (KMS) to sign<br/>This is different from the <code>signatureId</code> parameter that you provided in the request body. The <code>signatureId</code> parameter in the request body specifies the signature ID associated with the private key in KMS.

## Other responses

- `400`: Bad Request
- `401`: Unauthorized. Not valid or inactive subscription key present in the HTTP Header.
- `403`: Forbidden. The request is authenticated, but it is not possible to required perform operation due to logical error or invalid permissions.
- `500`: Internal server error. There was an error on the server during the processing of the request.

---

[API](https://skmtc.dev/tatum/apis/blockchain.md) - [All operations](https://skmtc.dev/tatum/apis/blockchain/llms.txt) - [OpenAPI document](https://skmtc.dev/tatum/apis/blockchain/revisions/f9623a85f420?raw)