If a validator shows harmful behavior, a percentage of their bonded/staked tokens will get slashed as a penalty, meaning they will lose them. 

If you were actively nominating that validator when the slash occurred, your tokens will get slashed too. This incentivizes good behavior and at the same time requires that you do your due diligence on vetting the validators you delegate your stake to, to be sure that you are aligned with their intentions. 

What could cause your tokens to get slashed?


Slashing will happen if a validator misbehaves (e.g. goes offline along many others, attacks the network, or runs modified software) in the network. The percentage of the total stake that gets slashed depends on the severity of the transgression.

It's worth noting that isolated offline events of a validator don't incur slashing. Instead, if a validator is offline for a prolonged time (at least 4 hours on Polkadot) they will instead get chilled, meaning they will stop validating and lose their nominators. Slashing for unavailability happens only if at least 10% of active validators go offline simultaneously, which could be an attack on the network.

What happens to the slashed tokens?

They will be added to the Treasury. This way, tokens from malicious actors are put towards projects by community members who actively help build the network and ecosystem. 

Read more about slashing in our Wiki.