Short answer. The estate satisfies a legacy of credit by assigning you all rights of action against the debtor, plus interest accrued by the testator's death. You receive the right to sue and collect, not cash, and only for the portion of the credit that still existed when the testator died.
What the law says
the estate shall comply with the legacy by assigning to the legatee all rights of action it may have against the debtor
Civil Code, Article 935 — Legacy of a Credit or a Remission of Debt. Read the full provision →
The estate gives you a right to sue, not cash
Article 935 of the Civil Code is precise about what the estate must deliver in a credit legacy: it must assign to you "all rights of action it may have against the debtor." You do not receive a check. You receive the legal standing to pursue the debtor yourself — to demand payment, to bring an action if needed, and to enforce any judgment. The estate steps out of the picture once the assignment is made. From that point, you are the creditor.
Interest is included
The article expressly provides that the legacy includes "all interests on the credit or debt which may be due the testator at the time of his death." So if the debtor owed the testator a principal sum plus accumulated interest that had not yet been paid by the date of death, the interest transfers to you along with the principal claim. The assignment covers the full accrued value of the obligation, not just the original face amount of the credit.
Only what remains at the testator's death
There is an important limit. The legacy is effective only as regards that part of the credit existing at the time of the death of the testator. If the debtor had already made partial payments to the testator before death, or if part of the credit was otherwise extinguished, the legacy covers only the surviving balance. The estate does not top up the amount to what was originally owed; you take the claim as the testator left it.
What you should expect from the estate
In practice, the assignment should be documented — a deed of assignment or similar instrument that identifies the credit, the debtor, and the amount being transferred, signed by the authorized representative of the estate. With that document in hand, you can approach the debtor, negotiate payment, or file suit if the debtor refuses to pay. If the estate delays or refuses to make the assignment, you may need to seek relief through estate settlement proceedings. Keeping records of what the testator was owed and when payments were made before death will help establish what portion of the credit properly belongs to you.