An address draws on a number (not just one) of unspent outputs. When a transaction is made, at least one entire output will be used, so until that transaction has received enough confirmations, the entire amount (of the formerly unspent output) will not be available for use.
- Alice’s current balance: 0.01 BTC, consisting of 4 unspent outputs (UTXOs), say 0.0025 BTC each
- Alice sends 0.0005 to Donald
- As a result, one entire UTXO was used (0.0025) so in Counterwallet she’ll see the amount of BTC available drop to 0.0075, and not to 0.0095 as one might expect
- As soon as the transaction receives enough confirmations, the amount jumps to 0.0095 BTC
####Appearance in the UI
Until pending transaction(s) are confirmed, the owner of this address can use only 0.00063375 BTC.
The larger amount in brackets (0.01) will become available once unconfirmed transactions related to this address receive 6 confirmations.