Hedera
  • Welcome to Hedera — let’s build the future
  • Getting Started
    • Environment Setup
    • Web2 Developers
      • Transfer HBAR
      • Create a Token
      • Create a Topic
    • EVM Developers
      • Deploy a Contract
  • Tutorials
    • Smart Contracts
      • How to Mint & Burn an ERC-721 Token Using Hardhat and Ethers (Part 1)
      • How to Set Access Control, a Token URI, Pause, and Transfer an ERC-721 Token Using Hardhat (Part 2)
      • How to Upgrade an ERC-721 Token with OpenZeppelin UUPS Proxies and Hardhat (Part 3)
      • How to Verify a Smart Contract on HashScan
      • Deploy a Smart Contract Using Remix
      • Deploy a Smart Contract Using Hardhat and Hiero JSON-RPC Relay
      • Deploy Your First Smart Contract
      • Deploy a Contract Using the Hedera Token Service
      • Send and Receive HBAR Using Solidity Smart Contracts
      • Deploy By Leveraging Ethereum Developer Tools On Hedera
      • Deploy a Subgraph Using The Graph and Hedera JSON-RPC Relay
      • Deploy Smart Contracts on Hedera Using Truffle
      • The Power of Native Hedera Tokens as ERC-20 Tokens: A step-by-step guide
      • HTS x EVM - Part 1: How to Mint NFTs
      • HTS x EVM - Part 2: KYC & Update
      • HTS x EVM - Part 3: How to Pause, Freeze, Wipe, and Delete NFTs
      • Hedera Smart Contracts Workshop
        • Setup
        • Solidity
        • Hedera SDK JS
        • Hardhat and EthersJs
        • Outro
      • Foundry
        • How to Setup Foundry and Write a Basic Unit Test
        • How to Deploy and Verify a Hedera Smart Contract with Foundry
        • How to Test A Solidity Event
        • How to Fork Testnet on Latest Block
    • Consensus
      • Submit Your First Message
      • Submit Message to Private Topic
      • Query Messages with Mirror Node
    • Tokens
      • Create and Transfer Your First NFT
      • Create and Transfer Your First Fungible Token
      • Create and Transfer an NFT using a Solidity Contract
      • Structure Your Token Metadata Using JSON Schema V2
      • Hedera Token Service - Part 1: How to Mint NFTs
      • Hedera Token Service - Part 2: KYC, Update, and Scheduled Transactions
      • Hedera Token Service - Part 3: How to Pause, Freeze, Wipe, and Delete NFTs
      • Create Your First Frictionless Airdrop Campaign
    • Local Node
      • How to Run Hedera Local Node in a Cloud Development Environment (CDE)
        • Run a Local Node in Gitpod
        • Run a Local Node in Codespaces
      • How to Set Up a Hedera Local Node
      • Set Up a Hedera Local Node using the NPM CLI
    • More Tutorials
      • Create and Fund Your Hedera Testnet Account
      • How to Create a Personal Access Token (API Key) on the Hedera Portal
      • How to Auto-Create Hedera Accounts with HBAR and Token Transfers
      • How to Configure a Mirror Node and Query Data
      • How to Generate a Random Number on Hedera
      • Get Started with the Hedera Consensus Service Fabric Plugin
        • Virtual Environment Setup
      • Schedule Your First Transaction
      • How to Connect to Hedera Networks Over RPC
        • Configuring Hashio RPC endpoints
        • Configuring Hiero JSON-RPC Relay endpoints
        • Configuring Validation Cloud RPC endpoints
      • JavaScript Testing
      • Create a Hedera DApp Integrated with WalletConnect
      • How to Connect MetaMask to Hedera
    • Demo Applications
    • Starter Projects
    • Building on Hedera (course)
  • Networks
    • Mainnet
      • Mainnet Accounts
      • Mainnet Consensus Nodes
        • Node Requirements
          • FAQ
      • Fees
        • Transaction Records
    • Testnets
      • Testnet Accounts
      • Testnet Consensus Nodes
    • Localnet
      • Single Node Configuration
      • Multinode Configuration
    • Network Explorers and Tools
    • Release Notes
      • Consensus Node
      • Hedera Mirror Node
  • Core Concepts
    • Accounts
      • Account Creation
      • Auto Account Creation
      • Account Properties
    • Keys and Signatures
    • Schedule Transaction
    • Smart Contracts
      • Understanding Hedera's EVM Differences and Compatibility
        • For EVM Developers Migrating to Hedera
          • Accounts, Signature Verification & Keys (ECDSA vs. ED25519)
          • JSON-RPC Relay and EVM Tooling
          • Token Management with Hedera Token Service
          • Decimal Handling (8 vs. 18 Decimals)
          • Handling HBAR Transfers in Contracts
        • For Hedera-Native Developers Adding Smart Contract Functionality
          • Integrating ED25519 Accounts and Advanced Features Into Smart Contracts
          • JSON-RPC Relay and State Queries
          • Extending Token Management with Smart Contracts
      • Creating Smart Contracts
      • Compiling Smart Contracts
      • System Smart Contracts
        • Hedera Account Service
        • Hedera Schedule Service
      • Gas and Fees
      • JSON-RPC Relay
      • Deploying Smart Contracts
      • Smart Contract Addresses
      • Verifying Smart Contracts
      • Smart Contract Traceability
      • Tokens Managed by Smart Contracts
        • ERC-20 (Fungible Tokens)
        • ERC-721 (Non-Fungible Token)
        • ERC-3643 Real World Assets (RWA)
        • ERC-1363 (Payable Tokens)
        • Hedera Token Service System Contract
      • Wrapped HBAR (WHBAR)
      • Smart Contract Rent
      • Smart Contract Security
      • EVM Archive Node Queries
    • Tokens
      • Tokenization on Hedera
      • Hedera Token Service (HTS) Native Tokenization
        • Token Types and ID Formats
        • Token Properties
        • Token Creation
        • Custom Fee Schedule
        • Token Airdrops
      • ERC/EVM-Compatible Tokenization
      • Hybrid (HTS + EVM ) Tokenization
    • Staking
      • Staking Program
      • Stake HBAR
    • Hashgraph Consensus Algorithm
      • Gossip About Gossip
      • Virtual Voting
    • Transactions and Queries
      • Transaction Properties
    • State and History
    • Mirror Nodes
      • Hedera Mirror Node
      • One Click Mirror Node Deployment
      • Run Your Own Mirror Node
        • Run Your Own Mirror Node with Google Cloud Storage (GCS)
        • Run Your Mirror Node with Amazon Web Services S3 (AWS)
  • Open Source Solutions and Integrations
    • AI Studio on Hedera
      • ElizaOS Plugin for Hedera
      • Hedera AI Agent Kit
      • MCP Server
      • OpenConvAI
    • AI Tools for Developers
      • Hedera Hivemind
      • Kapa AI
    • Asset Tokenization Studio (ATS)
      • Web User Interface (UI)
      • Frequently Asked Questions (FAQs)
    • HashioDAO
      • Governance Token DAO
      • NFT DAO
      • Multisig DAO
      • DAO Proposals
      • Local Environment Setup
    • Hedera CLI
    • Hedera Contract Builder
    • Hedera Custodians Library
      • How to use it
    • Hedera Developers Code Repository
    • Hedera Developer Playground
    • Hedera Wallet Snap By MetaMask
      • Hedera Wallet Snap Documentation
      • Tutorial: MetaMask Snaps – What Are They and How to Use Them
    • Interoperability and Bridging
      • LayerZero
    • NFT Studio
      • Airdrop List Verifier
      • Metadata Validator
      • NFT Rarity Inspector
      • NFT Token Holders List Builder
      • NFT Risk Calculator
      • Token Balance Snapshot
      • Hedera NFT SDK
    • Oracle Networks
      • Chainlink Oracles
      • Pyth Oracles
      • Supra Oracles
    • Stablecoin Studio
      • Core Concepts
      • Web UI Application
      • CLI Management
      • TypeScript SDK
    • Hedera Guardian
    • Hedera WalletConnect
  • SDKs & APIs
    • SDKs
      • Build Your Hedera Client
      • Set Up Your Local Network
      • Network Address Book
      • Keys
        • Generate a new key pair
        • Import an existing key
        • Create a key list
        • Create a threshold key
        • Generate a mnemonic phrase
        • Recover keys from a mnemonic phrase
      • HBAR
      • Specialized Types
      • Pseudorandom Number Generator
      • Transactions
        • Create a Batch Transaction
        • Transaction ID
        • Modify transaction fields
        • Create an unsigned transaction
        • Manually sign a transaction
        • Submit a transaction
        • Sign a multisignature transaction
        • Get a transaction receipt
        • Get a transaction record
      • Schedule Transaction
        • Schedule ID
        • Create a schedule transaction
        • Sign a scheduled transaction
        • Delete a schedule transaction
        • Get schedule info
        • Network Response Messages
      • Queries
      • General Network Response Messages
      • Accounts and HBAR
        • Create an account
        • Update an account
        • Transfer cryptocurrency
        • Approve an allowance
        • Delete an allowance
        • Delete an account
        • Get account balance
        • Get account info
        • Network Response Messages
      • Consensus Service
        • Create a topic
        • Update a topic
        • Submit a message
        • Delete a topic
        • Get topic messages
        • Get topic info
        • Network Response
      • Token Service
        • Token ID
        • NFT ID
        • Token types
        • Create a token
        • Custom token fees
        • Update a token
        • Update token custom fees
        • Update NFT metadata
        • Transfer tokens
        • Airdrop a token
        • Claim a token
        • Cancel a token
        • Reject a token
        • Delete a token
        • Mint a token
        • Burn a token
        • Freeze an account
        • Unfreeze an account
        • Enable KYC account flag
        • Disable KYC account flag
        • Associate tokens to an account
        • Dissociate tokens from an account
        • Pause a token
        • Unpause a token
        • Wipe a token
        • Atomic swaps
        • Get account token balance
        • Get token info
        • Get NFT info
        • Network Response Messages
      • File Service
        • Create a file
        • Append to a file
        • Update a file
        • Delete a file
        • Get file contents
        • Get file info
        • Network Response Messages
      • Smart Contract Service
        • Delegate Contract ID
        • Create a smart contract
        • Update a smart contract
        • Delete a smart contract
        • Call a smart contract function
        • Ethereum transaction
        • Get a smart contract function
        • Get smart contract bytecode
        • Get smart contract info
        • Hedera Service Solidity Libraries
        • Network Response Messages
      • Signature Provider
        • Provider
        • Signer
        • Wallet
        • Local Provider
    • Mirror Node REST API
      • Accounts
      • Balances
      • Blocks
      • Schedule Transactions
      • Smart Contracts
      • Tokens
      • Topics
      • Transactions
      • Network
    • Hedera Consensus Service gRPC API
    • Hedera APIs
      • Basic Types
        • AccountAmount
        • AccountID
        • ContractID
        • CryptoAllowance
        • CurrentAndNextFeeSchedule
        • FeeComponents
        • FeeData
        • FeeSchedule
        • FileID
        • Fraction
        • HederaFunctionality
        • Key
        • KeyList
        • NftAllowance
        • NftTransfer
        • NodeAddress
        • NodeAddressBook
        • RealmID
        • ScheduleID
        • SemanticVersion
        • ServicesConfigurationList
        • ServiceEndpoint
        • Setting
        • ShardID
        • Signature
        • SignatureList
        • SignatureMap
        • SignaturePair
        • SubType
        • TransferList
        • TransactionID
        • ThresholdKey
        • ThresholdSignature
        • TokenAllowance
        • TokenBalance
        • TokenBalances
        • TokenFreezeStatus
        • TokenPauseStatus
        • TokenID
        • TokenKycStatus
        • TokenRelationship
        • TokenTransferList
        • TokenType
        • TokenSupplyType
        • TopicID
        • TransactionFeeSchedule
      • Cryptocurrency Accounts
        • CryptoService
        • CryptApproveAllowance
        • CryptoDeleteAllowance
        • CryptoCreate
        • CryptoTransfer
        • CryptoUpdate
        • CryptoDelete
        • CryptoGetAccountBalance
        • CryptoGetAccountRecords
        • CryptoGetInfo
        • CryptoGetStakers
      • Consensus Service
        • Consensus Service
        • ConsensusCreateTopic
        • ConsensusUpdateTopic
        • ConsensusSubmitMessage
        • ConsensusDeleteTopic
        • ConsensusTopicInfo
        • ConsensusGetTopicInfo
      • Schedule Service
        • ScheduleService
        • SchedulableTransactionBody
        • ScheduleCreate
        • ScheduleDelete
        • ScheduleSign
        • ScheduleGetInfo
      • Token Service
        • TokenService
        • CustomFees
          • AssessedCustomFee
          • CustomFee
          • FractionalFee
          • FixedFee
          • RoyaltyFee
        • TokenCreate
        • TokenUpdate
        • TokenFeeScheduleUpdate
        • TokenDelete
        • TokenMint
        • TokenBurn
        • TokenFreezeAccount
        • TokenUnfreezeAccount
        • TokenGrantKyc
        • TokenRevokeKyc
        • TokenAssociate
        • TokenDissociate
        • TokenWipeAccount
        • TokenPause
        • TokenUnpause
        • TokenGetInfo
        • TokenGetNftInfo
        • TokenGetNftInfos
        • TokenGetAccountNftInfo
      • File Service
        • FileService
        • FileCreate
        • FileAppend
        • FileUpdate
        • FileDelete
        • FileGetContents
        • FileGetInfo
      • Smart Contracts
        • SmartContractService
        • ContractCall
        • ContractCallLocal
        • ContractCreate
        • ContractUpdate
        • ContractDelete
        • ContractGetByteCode
        • ContractGetInfo
        • ContractGetRecords
      • Miscellaneous
        • Duration
        • ExchangeRate
        • Freeze
        • FreezeType
        • GetByKey
        • GetBySolidityID
        • NetworkGetVersionInfo
        • NetworkService
        • Query
        • QueryHeader
        • Response
        • ResponseCode
        • ResponseHeader
        • SystemDelete
        • SystemUndelete
        • TimeStamp
        • Transaction
        • TransactionBody
        • TransactionContents
        • TransactionGetFastRecord
        • TransactionGetReceipt
        • TransactionGetRecord
        • TransactionReceipt
        • TransactionRecord
        • TransactionResponse
        • UncheckedSubmit
    • Hedera Status API
  • Support & Community
    • Glossary
    • Contributing to Hedera documentation
      • Contribution Guidelines
        • Creating Issues
        • Creating Pull Requests
        • Hedera Improvement Proposal (HIP)
        • Submit Demo Applications
      • Style Guide
        • Understanding different types of documentation
        • Use of HBAR and tinybars
        • Use of web2 and web3
        • Language and grammar
        • Formatting
        • Punctuation
        • GitBook Markdown Syntax
    • Discord
    • GitHub
    • Stack Overflow
    • Hedera Blog
    • Bug Bounty
    • Hedera Help
    • Documentation Survey
    • Meetups
    • Brand Guidelines
    • Status Page
Powered by GitBook
LogoLogo

INTRODUCTION

  • Fees
  • Core Concepts
  • Network Information

TOOLS

  • Bridge
  • Oracles
  • Explorers
  • Developer Portal & Faucet

RESOURCES

  • Status
  • Bug Bounty
  • Build on Hedera (course)
  • Documentation Survey
On this page

Was this helpful?

Edit on GitHub
  1. SDKs & APIs
  2. SDKs
  3. Consensus Service

Submit a message

PreviousUpdate a topicNextDelete a topic

Last updated 3 months ago

Was this helpful?

A transaction that submits a topic message to the Hedera network. To access the messages submitted to a topic ID, subscribe to the topic via a mirror node. The mirror node will publish the ordered messages to subscribers. Once the transaction is successfully executed, the receipt of the transaction will include the topic's updated sequence number and topic running hash.

Max Chunks

The max chunks setting defines the maximum number of chunks into which a given message can be split. The default value is 20 chunks, meaning a message can consist of up to 20 chunks by default. This value can be modified using the setMaxChunks method. Max Chunk Size

🚨 NOTE: Max size of an HCS message: 1024 bytes (1 kb).

The max chunk size refers to the maximum size (in bytes) of each individual chunk of a message. By default, the max chunk size is 1024 bytes (1 KB). This value can be modified using the setChunkSize method.

Custom Fee Payment

If a topic has custom fees enabled, users submitting messages must pay the required fee in HBAR or HTS fungible tokens. If setCustomFees is not specified in the transaction, the user would need to pay any fee associated with that topic ID. The transaction will only fail if the user does not have sufficient assets to cover the fee.

Recommendation: To avoid unexpected fees, it is strongly recommended to use setCustomFees when submitting a message. This ensures that only the intended fee structure is applied, providing a safeguard against unintended charges.

TopicMessageSubmitTransaction()
   .setTopicId(<TOPIC_ID>)
   .setMessage(<MESSAGE>)
   .setCustomFees(<MAX_CUSTOM_FEES>) // Ensure this covers the required amount
   .execute(client);

Transaction Signing Requirements

  • Anyone can submit a message to a public topic.

  • The submitKey is required to sign the transaction for a private topic.

Transaction Fees

  • Each transaction incurs a standard Hedera network fee based on network resource usage.

  • If a custom fee is set for a topic, users submitting messages must pay this fee in HBAR or HTS tokens.

  • The Fee Schedule Key allows authorized users to update fee structures. If set, it must sign transactions modifying fees.

  • If the topic has custom fees, the sender must have sufficient balance to cover the fees unless they are exempt via the Fee Exempt Key List. It is recommended to use setCustomFees on the TopicMessageSubmitTransaction to ensure the expected fee structure is applied and avoid unexpected transaction failures due to insufficient funds.

  • Use the to estimate standard network fees.

Methods

Method
Type
Description
Requirement

setTopicId(<topicId>)

TopicId

The topic ID to submit the message to

Required

setMessage(<message>)

String

The message in a String format

Optional

setMessage(<message>)

byte [ ]

The message in a byte array format

Optional

setMessage(<message>)

ByteString

The message in a ByteString format

Optional

setChunkSize()

int

The max size of individual chunk for a given message. Default: 1024 bytes

Optional

setMaxChunks()

int

The max number of chunks a given message can be split into. Default: 20

Optional

setMaxCustomFees()

Fee[]

The maximum custom fees the sender is willing to pay

Optional

//Create the transaction
TopicMessageSubmitTransaction transaction = new TopicMessageSubmitTransaction()
    .setTopicId(newTopicId)
    .setMessage("hello, HCS! ")
    .setMaxCustomFees(maxCustomFees); // Set max custom fees if applicable

//Sign with the client operator key and submit transaction to a Hedera network, get transaction ID
TransactionResponse txResponse = transaction.execute(client);

//Request the receipt of the transaction
TransactionReceipt receipt = txResponse.getReceipt(client);

//Get the transaction consensus status
Status transactionStatus = receipt.status;

System.out.println("The transaction consensus status is " +transactionStatus);

//v2.0.0
// Create the transaction
const transaction = await new TopicMessageSubmitTransaction()
    .setTopicId(newTopicId)
    .setMessage("Hello, HCS!")
    .setMaxCustomFees(maxCustomFees); // Set max custom fees if applicable

// Execute transaction
const txResponse = await transaction.execute(client);

// Request the receipt
const receipt = await txResponse.getReceipt(client);

// Get the transaction consensus status
console.log("Transaction Status:", receipt.status);

//v2.0.0
//Create the transaction
transaction := hedera.NewTopicSubmitTransaction().
        SetTopicID(topicID).
        SetMessage([]byte(content)).
        SetMaxCustomFees(maxCustomFees) // Set max custom fees if applicable

//Sign with the client operator private key and submit the transaction to a Hedera network
txResponse, err := transaction.Execute(client)
if err != nil {
        panic(err)
}

//Request the receipt of the transaction
transactionReceipt, err := txResponse.GetReceipt(client)
if err != nil {
        panic(err)
}

//Get the transaction consensus status
transactionStatus := receipt.Status

fmt.Printf("The transaction consensus status is %v\n", transactionStatus)

//v2.0.0

Get transaction values

Method
Type
Description

getTopicId()

TopicId

The topic ID to submit the message to

getMessage()

ByteString

The message being submitted

getAllTransactionHash()

byte [ ]

The hash for each transaction

getMaxCustomFees()

Fee[]

The max custom fees set for the message

//Create the transaction
TopicMessageSubmitTransaction transaction = new TopicMessageSubmitTransaction()
    .setTopicId(newTopicId)
    .setMessage("hello, HCS! ");

//Get the transaction message
ByteString getMessage = transaction.getMessage();
//v2.0.0
//Create the transaction
const transaction = await new TopicMessageSubmitTransaction()
    .setTopicId(newTopicId)
    .setMessage("hello, HCS! ");

//Get the transaction message
const getMessage = transaction.getMessage();

//v2.0.0
//Create the transaction
transaction := hedera.NewTopicSubmitTransaction().
        SetTopicID(topicID).
        SetMessage([]byte(content))

//Get the transaction message
getMessage := transaction.GetMessage()
//v2.0.0
Hedera Fee Estimator