Short answer. Generally no. Article 1298 says the novation is void if the original obligation was void — except when annulment may be claimed only by the debtor, or when ratification validates acts which are voidable. A truly void original debt has nothing to novate, so the new obligation built on it fails too, subject to those exceptions.
What the law says
The novation is void if the original obligation was void, except when annulment may be claimed only by the debtor or when ratification validates acts which are voidable.
Civil Code, Article 1298 — Void Original Obligation. Read the full provision →
A void original debt cannot be novated
Article 1298 gives the general answer here. It provides: The novation is void if the original obligation was void, except when annulment may be claimed only by the debtor or when ratification validates acts which are voidable. Novation works by extinguishing an old obligation and putting a new one in its place. But if the old obligation was void — a legal nullity that never existed in the eyes of the law — there is nothing there to extinguish and nothing to replace. The replacement built on top of that nullity collapses with it. As a rule, then, a novation of a void debt is itself void.
Why the old debt must be valid
The logic flows from what novation actually does. It is not the creation of a debt out of thin air; it is the substitution of one existing obligation for another. That structure needs a genuine, subsisting first obligation to operate on. When the original is void, the foundation is missing. Treating the new contract as valid would let parties launder a legally non-existent debt into an enforceable one just by rewriting it — exactly what Article 1298 refuses to allow. The nullity of the source contaminates the substitute, because the substitute depends on there having been something real to replace.
Void is not the same as voidable
The article turns on a distinction that decides many cases: void versus voidable. A void obligation is a nullity from the beginning and produces no effects. A voidable one is valid and binding until it is annulled — it exists and can be confirmed. Article 1298's rule of nullity is aimed at truly void originals. Where the original was merely voidable, it may still support a novation, because it was not a legal nothing to begin with. Knowing which category your original debt falls into is therefore the first question: it changes whether the new obligation stands or falls.
The two exceptions
The article itself carves out two situations where the novation survives despite a defect in the original. First, when annulment may be claimed only by the debtor — where the flaw is one the debtor alone could have used to escape, his agreement to a new obligation can effectively waive it. Second, when ratification validates acts which are voidable — a voidable original can be confirmed, and once ratified it supports the novation as if it had always been valid. Both exceptions share a theme: the original was not a genuine nullity but a curable defect, and the debtor's own conduct cured it.