Short answer. Yes. Rule 6, Section 5 lists the statute of limitations — prescription — as an affirmative defense, which is pleaded in the answer itself rather than in a separate motion to dismiss. You still need to allege the facts showing when the period to sue began and why it has already run.
What the law says
An affirmative defense is an allegation of a new matter which, while hypothetically admitting the material allegations in the pleading of the claimant, would nevertheless prevent or bar recovery by him or her. The affirmative defenses include fraud, statute of limitations, release, payment, illegality, statute of frauds, estoppel, former recovery, discharge in bankruptcy, and any other matter by way of confession and avoidance.
Rule 6, Section 5 — Defenses. Read the full provision →
Prescription is an affirmative defense, not a denial
Rule 6, Section 5 defines an affirmative defense as new matter which, even while hypothetically admitting everything the plaintiff alleges, would still prevent or bar recovery. The rule's own list of affirmative defenses names the statute of limitations — the deadline within which a claim must be filed — alongside fraud, payment, release, illegality, and estoppel. Prescription fits this description exactly: it does not dispute that the underlying obligation or wrong existed, it says the window for suing over it has already closed. That is why it is pleaded as an affirmative defense rather than as a specific denial.
Raising it in the answer instead of a separate motion
Because prescription sits on the affirmative-defense list, a defendant states it directly in the answer, in the same pleading that responds to the rest of the complaint, rather than filing it as a stand-alone motion before answering. This keeps the timeline objection before the court together with any other defenses raised, and puts the plaintiff on notice of it from the very first responsive pleading, so both sides and the court are working from a complete picture of the defense from the start of the case.
You still have to plead the facts, not just the label
Simply writing the word prescription in the answer is not enough. An affirmative defense is defined as an allegation of new matter — meaning the defendant has to state the facts that make the period run out: when the cause of action arose or was discovered, what the applicable period is, and why that period has already elapsed by the time the complaint was filed. Without those specifics, the defense is a conclusion rather than the kind of allegation the rule describes, and it hypothetically admits the claimant's allegations only to the extent the new matter actually bars them.
How it differs from disputing the facts themselves
A negative defense — a specific denial — says a fact the plaintiff alleges is not true. Prescription does the opposite: for purposes of the defense, it assumes the plaintiff's version of events is accurate and argues that even so, recovery is barred because too much time has passed. That is exactly what the rule means by confession and avoidance — conceding the point hypothetically while raising something new that defeats it anyway — and it is why prescription belongs with fraud and payment on the affirmative-defense list rather than among ordinary denials.