Extension Wallet
Integration
BITCOIN Network
Send And Push Tx

Send BTC & Push Tx

This section covers two different “broadcast” flows supported by the Cosmostation Bitcoin provider:

  • Send BTC (sendBitcoin): the wallet constructs + signs + broadcasts a BTC transfer for you
  • Push Tx (pushTx): you provide a fully-signed raw transaction hex and the wallet broadcasts it

Both methods require a wallet connection first.

Send BTC (sendBitcoin)

sendBitcoin(to, satAmount) is the simplest way to transfer BTC from the currently selected wallet account.

  • The wallet handles UTXO selection, fee calculation (wallet policy), signing, and broadcast.
  • satAmount is expressed in satoshis (1 BTC = 100,000,000 sats).
  • The return value is typically a transaction id (txid) string.

SDK Integration (Tomo Wallet SDK)

<LodingButton
  disabled={!btcIsConnect}
  onClick={async () => {
    try {
      const result = await providers.bitcoinProvider?.sendBitcoin(bitcoinAddress, 1300);
      console.log(`send btc to ${bitcoinAddress}`, result);
    } catch (e) {
      console.log(e);
    }
  }}
>
  send btc()
</LodingButton>

Vanilla JavaScript

const bitcoin = () => {
  if ('cosmostation' in window) return window.cosmostation.bitcoin;
  window.open('https://cosmostation.io/wallet/#extension');
};
 
const provider = bitcoin();
 
await provider.connectWallet();
 
try {
  const to = 'bc1q...'; // receiver address
  const satAmount = 1300;
 
  const txid = await provider.sendBitcoin(to, satAmount);
  console.log('sendBitcoin txid:', txid);
} catch (e: any) {
  if (e?.code === 4001) console.log('User rejected the request');
  else console.error(e);
}

Push Tx (pushTx)

pushTx(txHex) broadcasts a fully signed raw Bitcoin transaction.

Use this when your app already produced the final transaction hex, such as:

  • your dApp builds and signs externally (or via PSBT finalize)
  • you already have a canonical raw transaction and only need broadcast

The wallet/provider does not sign anything here — it only broadcasts.

SDK Integration (Tomo Wallet SDK)

<LodingButton
  disabled={!btcIsConnect}
  onClick={async () => {
    try {
      const result = await providers.bitcoinProvider?.pushTx(
        '02000000000102...00000000', // raw tx hex (signed)
      );
 
      console.log('pushTx result:', result);
    } catch (e) {
      console.log(e);
    }
  }}
>
  btc PushTx()
</LodingButton>

What this does

  • Submits the raw transaction hex to the provider
  • Returns a txid (or a broadcast result) if accepted by the network/mempool layer

Vanilla JavaScript

const bitcoin = () => {
  if ('cosmostation' in window) return window.cosmostation.bitcoin;
  window.open('https://cosmostation.io/wallet/#extension');
};
 
const provider = bitcoin();
 
await provider.connectWallet();
 
try {
  const txHex = '02000000000102...00000000'; // fully signed raw tx hex
  const txid = await provider.pushTx(txHex);
 
  console.log('pushTx txid:', txid);
} catch (e: any) {
  if (e?.code === 4001) console.log('User rejected the request');
  else console.error(e);
}

Important notes

  • txHex must be a valid, fully signed Bitcoin transaction.

  • Broadcast may fail if:

    • inputs are already spent
    • fee rate is too low / mempool policy rejection
    • transaction is invalid for the current network (mainnet vs testnet/signet)

  • If your transaction came from a PSBT flow:

    • sign PSBT → finalize PSBT → extract raw tx hex → pushTx(txHex)

Reference

For exact method signatures, provider behavior, and working demo patterns, refer to:

Sign PsbtSign Message