Rootstock Smart Bitcoin wallet

What is Bitcoin on Rootstock (RBTC)?

RBTC is what Bitcoin becomes when it crosses into Rootstock, a sidechain that adds EVM smart contracts to Bitcoin and is secured by merge mining with Bitcoin miners. The peg runs in both directions through the PowPeg: BTC is locked on the Bitcoin side and the same amount of RBTC appears on Rootstock, one for one, and the reverse unlocks it.

The defining practical fact is that RBTC is not a token on Rootstock, it is the network's native coin. It pays gas there, the way ETH does on Ethereum. So there is no contract address to add and no separate fee coin to keep: the thing you hold is the thing that pays for moving it. Balances are addressed with EVM-style addresses, and Rootstock uses its own checksum convention, which is why an address can look subtly different from the same string elsewhere.

Separately, wrapped representations of RBTC exist on other chains as ordinary tokens. Those are contracts, not the native coin, they carry the usual bridge dependency, and they require that chain's own coin for fees. A balance labelled RBTC therefore means different things depending on where it lives, and pegged to BTC is not the same as being BTC on the Bitcoin network.

Tangem keeps a separate balance per network and states, on the confirmation screen, which network an outgoing transfer will use, so read that line before the card signs, especially since an EVM address looks the same across chains. Supported networks in Tangem (5): Rootstock RSK, Arbitrum One, Base, Ethereum, Solana. Where one asset appears in native and wrapped forms at once, that separation is worth having.