Dev Docs

Sending Transactions

This page goes over how to build an inbound THORChain transaction for each chain type.
Confirm you have:
  • Connected to Midgard or THORNode
  • Located the latest vault (and router) for the chain
  • Prepared the transaction details (and memo)
  • Checked the network is not halted for your transaction
You are ready to make the transaction and swap via THORChain.

UTXO Chains

  • Send the transaction with Asgard vault as VOUT0
  • Include the memo as an OP_RETURN in VOUT1
  • Pass all change back to the VIN0 address in VOUT3
  • Use a high enough gas_rate to be included
  • Do not send below the dust threshold (10k Sats BTC, BCH, LTC, 1m DOGE), exhaustive values can be found on the Inbound Addresses endpoint
Inbound transactions should not be delayed for any reason else there is risk funds will be sent to an unreachable address. Use standard transactions, check the Inbound_Address before sending and use the recommended gas rate to ensure transactions are confirmed in the next block to the latest Inbound_Address.
Memo limited to 80 bytes on BTC. Use abbreviated options and THORNames where possible.
Do not use HD wallets that forward the change to a new address, because THORChain IDs the user as the address in VIN0. The user must keep their VIN0 address funded for refunds.
Override randomised VOUT ordering; THORChain requires specific output ordering.

EVM Chains

depositWithExpiry(vault, asset, amount, memo, expiry)
  • If ERC20, approve the router to spend an allowance of the token first
  • Send the transaction as a depositWithExpiry() on the router
  • Vault is the Asgard vault address, asset is the token address to swap, memo as a string
  • Use an expiry which is +60mins on the current time (if the tx is delayed, it will get refunded)
  • Use a high enough gas_rate to be included, otherwise the tx will get stuck
ETH is 0x0000000000000000000000000000000000000000
ETH is sent and received as an internal transaction. Your wallet may not be set to read internal balances and transactions

BFT Chains

  • Send the transaction to the Asgard vault
  • Include the memo
  • Only use the base asset as the choice for gas asset


To initiate a $RUNE -> $ASSET swap a MsgDeposit must be broadcasted to the THORChain blockchain. The MsgDeposit does not have a destination address, and has the following properties. The full definition can be found here.
Coins: coins,
Memo: memo,
Signer: signer,
If you are using Javascript, CosmJS is the recommended package to build and broadcast custom message types. Here is a walkthrough.