Scheme code system · Mastercard
Official, limited scope51
Insufficient funds/over credit limit
Available funds or credit are insufficient for the requested amount.
- Outcome
- Declined
- Code system
- Mastercard
- Raw format
- Two-character DE 39 response code
Operational context
Evaluate the advice code
For merchant-initiated transactions, evaluate DE 39 together with DE 48.84 Merchant Advice Code. MAC 02 means wait 24 hours; MAC 03 or 21 means do not retry.
Explicit mapping
SchemeLens concepts
These links are editorial mappings, not replacements for the raw source value. The relation shows how closely the wording aligns.
| Concept | Relation | Mapping note |
|---|---|---|
| Insufficient funds | Broader than concept | Mastercard combines insufficient funds and an over-credit-limit condition in this public wording. |
Namespace check
The same raw value exists elsewhere
- Visa 51Not sufficient funds
- UnionPay 51Available funds are insufficient
- EBANX 51Available funds are insufficient
Provenance
Sources used for this record
- Mastercard: Transaction Processing RulesOfficial source for published DE 39 values and selected Merchant Advice Code rules; not a complete public technical specification.9 December 2025
SchemeLens keeps source wording, normalized concepts, and operational guidance separate so later evidence can be added without rewriting the raw record.