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Visa

Visa Issuer Response Code 51: Not Sufficient Funds

soft decline

Last updated: October 8, 2026

Key details

Brand
Visa
Code
51
Response
51
Detailed Response
Not sufficient funds
soft decline
This transaction is retriable

Payments failing with code 51 are often recoverable with the right retry timing and routing. SmartRetry recovers up to 70% of soft declines with smart retries!

Actually, a big part of your declined transactions can be recovered

Recover your revenue >

What it means

Visa issuer response code 51 indicates that the cardholder's account or available credit limit does not have enough funds to cover the requested transaction amount at the time of authorization. It is a financial decline sent directly by the issuing bank rather than a technical or fraud-related block.

Why does code 51 occur?

  • The cardholder's bank account balance is lower than the requested transaction amount.
  • The transaction exceeds the available credit limit on the cardholder's credit card.
  • Previous authorization holds have temporarily reduced the available balance on the account.

How to solve 51?

To resolve this decline, the underlying account balance or available credit must increase to cover the requested amount, or the customer must supply a different, fully funded payment method. Immediate, blind resubmissions of the exact same amount without a change in account status will likely result in repeated declines.

Solving as a merchant

Preserve the original decline response and communicate to the customer that the payment failed due to insufficient funds. Prompt them to add funds to their account or provide an alternative payment method. If utilizing automated retry logic, employ a small, spaced retry budget that respects the maximum network limit (15 attempts in 30 days) and stop immediately if an alternate payment method is provided.

Solving as a client

Check the available balance or credit limit on the account to ensure enough funds exist to complete the purchase. Either add necessary funds, pay down an existing credit balance, or provide a different payment method.

Tip from SmartRetry Schedule retries around common payroll cycles—such as the 1st and 15th of the month or Friday mornings—rather than firing rapid resubmissions. This gives cardholders time to replenish their balance while protecting your authorization health with issuing banks.

See the full list of Visa's decline codes >Find code on Visa's website >

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Kyle Regacho

Author

Kyle Regacho
LinkedInFind me on Linkedin

Focused on payment recovery, decline codes, and authorization optimization at SmartRetry. Helps payment teams turn failed transactions into recovered revenue

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Decline codes tell you why. We fix it.

SmartRetry reads every decline reason and applies the right retry strategy for each one. Your recovery rate goes up without any changes to your payment provider.