> ## Documentation Index
> Fetch the complete documentation index at: https://docs.gelato.cloud/llms.txt
> Use this file to discover all available pages before exploring further.

# relayer_sendTransactionSync

> Submits a signed transaction intent to the relayer for on-chain execution and waits for the transaction to be included. Returns the transaction receipt upon success. This is a synchronous version of relayer_sendTransaction that waits for the transaction to complete.



## OpenAPI

````yaml /gasless-with-relay/relayer-api-endpoints/relay/relayer_sendTransactionSync.json post /rpc
openapi: 3.1.0
info:
  title: relayer_sendTransactionSync
  version: 1.0.0
servers:
  - url: https://api.gelato.cloud
    description: Mainnet
security: []
paths:
  /rpc:
    post:
      summary: relayer_sendTransactionSync
      description: >-
        Submits a signed transaction intent to the relayer for on-chain
        execution and waits for the transaction to be included. Returns the
        transaction receipt upon success. This is a synchronous version of
        relayer_sendTransaction that waits for the transaction to complete.
      parameters:
        - name: X-API-Key
          in: header
          required: true
          schema:
            type: string
          description: Gelato API key for authentication.
      requestBody:
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/Request'
        required: true
      responses:
        '200':
          description: Successful response
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Response'
        '400':
          description: Validation error
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
        '401':
          description: Unauthorized
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/ErrorResponse'
components:
  schemas:
    Request:
      type: object
      required:
        - jsonrpc
        - method
        - params
        - id
      properties:
        id:
          type: number
          default: 1
        jsonrpc:
          type: string
          default: '2.0'
        method:
          type: string
          default: relayer_sendTransactionSync
        params:
          $ref: '#/components/schemas/SendTransactionSyncParams'
    Response:
      type: object
      properties:
        id:
          type: number
          default: 1
        jsonrpc:
          type: string
          default: '2.0'
        result:
          $ref: '#/components/schemas/TransactionReceipt'
    ErrorResponse:
      type: object
      properties:
        jsonrpc:
          type: string
          default: '2.0'
        id:
          type: number
        error:
          type: object
          properties:
            code:
              type: number
              description: >-
                Error code (-32602: Invalid params, 4100: Unauthorized, 4200:
                Insufficient Payment, 4201: Invalid Signature, 4202: Unsupported
                Payment Token, 4204: Quote Expired, 4205: Insufficient Balance,
                4206: Unsupported Chain, 4210: Invalid Authorization List, 4211:
                Simulation Failed)
            message:
              type: string
              description: Error message
    SendTransactionSyncParams:
      type: object
      required:
        - chainId
        - payment
        - to
        - data
      properties:
        chainId:
          type: string
          description: Chain ID
          default: '137'
        payment:
          $ref: '#/components/schemas/Payment'
        to:
          type: string
          description: Target contract address
          default: '0x55f3a93f544e01ce4378d25e927d7c493b863bd7'
        data:
          type: string
          description: Encoded transaction data
          default: 0x29cb0f49...
        context:
          type: string
          description: >-
            Context from relayer_getFeeData (optional, required for token
            payments)
        authorizationList:
          type: array
          description: >-
            EIP-7702 authorization list for upgrading EOAs to smart accounts
            (optional)
          items:
            $ref: '#/components/schemas/Authorization'
        timeout:
          type: number
          description: Timeout in milliseconds to wait for transaction inclusion (optional)
          example: 60000
    TransactionReceipt:
      type: object
      description: Transaction receipt returned when transaction is included on-chain
      properties:
        transactionHash:
          type: string
          description: Transaction hash
          example: '0x0e670ec64341771606e55d6b4ca35a1a6b75ee3d5145a99d05921026d1527331'
        blockNumber:
          type: string
          description: Block number where transaction was included
        blockHash:
          type: string
          description: Block hash
        gasUsed:
          type: string
          description: Gas used by the transaction
        status:
          type: number
          description: Transaction status (1 = success, 0 = failure)
    Payment:
      type: object
      required:
        - type
      properties:
        type:
          type: string
          enum:
            - sponsored
          description: 'Payment type: ''sponsored'' (relayer pays gas from Gas Tank)'
          default: sponsored
    Authorization:
      type: object
      description: EIP-7702 authorization for upgrading EOAs to smart accounts
      properties:
        address:
          type: string
          description: Smart account implementation address
        chainId:
          type: number
          description: Chain ID for the authorization
        nonce:
          type: number
          description: Authorization nonce
        r:
          type: string
          description: ECDSA signature r value
        s:
          type: string
          description: ECDSA signature s value
        yParity:
          type: number
          description: ECDSA signature y parity (0 or 1)

````