Solana rent is a mechanism that requires on-chain accounts to hold a minimum SOL balance proportional to their data size. This prevents the network from being filled with unused accounts consuming storage.

Accounts that maintain a balance above the rent-exempt threshold do not pay ongoing rent — they are rent-exempt. The rent-exempt threshold is approximately 0.002 SOL for a typical token account.

When an account is closed on Solana — such as when a token lock expires and the lock account is closed — the rent deposit is returned to the wallet that created it. This means most Solana operations are fully reversible in terms of rent costs.