Dusting

The sending of very small amounts of cryptocurrency (“dust”) to target addresses, sometimes to encourage activity that may reveal links between addresses. In the UTXO model, an address whose outputs have been fully spent may remain unused and unlinked to the owner's other addresses, although address reuse and other tracing heuristics can still establish connections. Sending dust creates a new spendable output associated with the target address. If the owner's wallet later spends that output together with other inputs, for example during consolidation or automatic coin selection, the common-input heuristic may link the input addresses as being under common control. The sender can identify the dust output they created and monitor where it goes, but cannot determine which other inputs will be spent with it in advance.

On account-based networks, there is no equivalent common-input heuristic, so dusting is more commonly associated with spam, advertising and address poisoning. Receiving dust does not demonstrate any action by the recipient. If the recipient later spends it alongside other UTXOs, the resulting link carries the usual evidential weight and limitations of the common-input heuristic, including exceptions such as CoinJoin and PayJoin. Some wallets allow users to flag suspicious outputs as “do not spend”.