How long does a Kaspa transaction stay pending in the mempool?

How long a Kaspa transaction stays pending depends on how it entered the mempool — the waiting area where unconfirmed transactions queue before being added to the blockDAG. Transactions relayed peer-to-peer between nodes expire after 60 blocks if they have not been included in the blockDAG during that window. Transactions submitted via RPC — the channel wallets use to talk directly to a node — never expire; they are periodically rebroadcast to the network until they confirm or the node is restarted. This matters because a wallet-submitted transaction that gets stuck will keep retrying indefinitely, while a peer-relayed transaction that goes too long without confirmation will quietly disappear on its own.