How to Bridge Ethereum to Binance Smart Chain
The best way to bridge Ethereum (ETH) to Binance Smart Chain with USD stablecoins like USDT or USDC is with Synapse Protocol.
They are the largest and most liquid cross-chain DEX that allows users to swap tokens between two networks like Ethereum Mainnet and BNB Chain. Their platform allows you to bridge a variety of tokens like ETH, USDC, USDT, DAI, BUSD and more with minimal fees and low slippage to the Binance Smart Chain network from Ethereum mainnet.
It is probably more convenient to transfer USDT, USDC or ETH into BUSD instead of keeping it as the original token. This is because BUSD is the major liquidity pair on the BNB Network, which means you will get better liquidity for on-chain swaps.
How to Convert ETH to BNB on Metamask
You cannot directly convert ETH to BNB on your Metamask wallet. You will need to first bridge stablecoins to the Binance Smart Chain (as shown above), then visit a BSC DEX like PancakeSwap to trade your BUSD for BNB.
The conversion fee from Ethereum to Binance Coin (BNB) is very low thanks to the BSC Chain's cheap fees. It will cost you a maximum of 10 cents to swap ETH to BNB on PancakeSwap or an equivalent DEX.
Bridge BNB to ETH
If you are looking to bridge your BNB back to ETH, you can follow the exact same process with Synapse Protocol. Simply select BNB Chain as your current network, then Ethereum Mainnet as your destination network and complete the transfer.
The BNB to ETH swap will cost up to $1 because a cross-chain transfer requires more blockspace. The demand for blockspace in a transaction is ultimately what sets the fee on BSC and other networks.