BTC Bridging is ONLY available through the Core Extension.
The Bridge Web UI (core.app\bridge) does not currently support Core Extension, but full support is coming soon.
The “.b” indicates that the token was bridged from the Bitcoin network, just as Avalanche Bridge™ tokens bridged from Ethereum end in “.e”.
At this time, the Core Wallet supports "Native Segwit" addresses for BTC withdrawals and these start with - bc1q.
The Core Extension will need to have Bitcoin (BTC) before bridging over assets.
Bridging BTC to Avalanche
1. Select the network to move assets. The image below shows the three possible networks (Avalanche, Ethereum, and Bitcoin). In our example, we will select “Bitcoin”.
2. Enter the amount of Bitcoin to Bridge over, and select "Transfer".
3. Once the BTC has been successfully bridged over, it will appear in your Bitcoin Portfolio.
The Core extension supports bridging between the Avalanche C-chain, and Bitcoin.
As a reminder, there are two distinct types of fees for the BTC Bridge:
Network fees, known as BTC transaction (Tx) fees for the BTC Bridge.
Fees that are charged by the Bridge to the user (also known as Bridge Toll).
If the transaction is not going through, this may be due to an inadequate amount of BTC to cover the fees. Please check before sending to ensure there is enough BTC to cover the fees.
Bitcoin that is bridged will now appear with a ".b" designation representing the bridged asset.
The Core interface will need time to update your newly bridged asset.
For any additional questions regarding the BTC Bridge, please visit the following page.
For a more in-depth read on how the Avalanche Bridge works, please read the following articles.