| Code | Description | Relevant nuts |
|---|---|---|
| 10002 | Blinded message of output already signed | NUT-03, NUT-04, NUT-05 |
| 10003 | Token could not be verified | NUT-03, NUT-05 |
| 11001 | Token is already spent | NUT-03, NUT-05 |
| 11002 | Transaction is not balanced (inputs != outputs) | NUT-02, NUT-03, NUT-05 |
| 11005 | Unit in request is not supported | NUT-04, NUT-05 |
| 11006 | Amount outside of limit range | NUT-04, NUT-05 |
| 12001 | Keyset is not known | NUT-02, NUT-04 |
| 12002 | Keyset is inactive, cannot sign messages | NUT-02, NUT-03, NUT-04 |
| 20001 | Quote request is not paid | NUT-04 |
| 20002 | Tokens have already been issued for quote | NUT-04 |
| 20003 | Minting is disabled | NUT-04 |
| 20005 | Quote is pending | NUT-04, NUT-05 |
| 20006 | Invoice already paid | NUT-05 |
| 20007 | Quote is expired | NUT-04, NUT-05 |