Short answer. Yes. Civil Code Article 952 states that legacies of money must be paid in cash, even though the heir or the estate may not have any. The heirs cannot substitute property or other assets for a cash legacy simply because the estate lacks ready money on hand.
What the law says
Legacies of money must be paid in cash, even though the heir or the estate may not have any.
Civil Code, Article 952 — The Very Thing Must Be Delivered. Read the full provision →
The general rule: deliver the thing itself
Article 952 opens with the broader principle governing how any legacy is satisfied: the heir, charged with a legacy or devise, or the executor or administrator of the estate, must deliver the very thing bequeathed if he is able to do so and cannot discharge this obligation by paying its value. Ordinarily, then, a legacy of a specific item has to be delivered as that item, not swapped out for its cash equivalent, because the testator's actual intent was to give that particular thing.
Why cash legacies get an even stricter rule
For a legacy of money, the article applies the same logic in the other direction, and makes it explicit: legacies of money must be paid in cash, even though the heir or the estate may not have any. Where the general rule bars substituting cash for a specific thing, this sentence bars substituting property or other assets for cash the testator specifically bequeathed. The estate's own lack of ready money is not a legal excuse to hand you property instead; the obligation is to produce cash, however the estate has to arrange that.
Who bears the cost, and what it does not override
Article 952 also addresses the practical cost of complying: the expenses necessary for the delivery of the thing bequeathed shall be for the account of the heir or the estate, meaning the heir or estate, not you, generally bears the cost of raising or delivering the money. That obligation, though, comes with an important limit built into the same sentence: it applies without prejudice to the legitime, the portion of the estate reserved by law for compulsory heirs. A cash legacy cannot be enforced in a way that eats into what the law reserves for those compulsory heirs.
What this means practically for the heirs
Because the estate cannot substitute property for the cash you are owed, the heirs or the administrator generally have to convert other estate assets into cash, whether by selling property, collecting on receivables, or otherwise raising funds, in order to satisfy your legacy in the form the testator specified. Delays in the estate's liquidity are a practical problem for the estate to solve, not a legal basis for changing what you are entitled to receive. That said, how quickly the money is actually raised and paid out can still depend heavily on the estate's specific assets and the state of its settlement.