Short answer. Article 283 conditions a valid redundancy termination on the employer serving written notice on the workers and the labor authorities at least one month before the date. It states no specific penalty for skipping that notice, but the notice requirement and your right to separation pay both come from this same text.
What the law says
Closure of establishment and reduction of personnel. The employer may also terminate the employment of any employee due to the installation of labor-saving devices, redundancy, retrenchment to prevent losses or the closing or cessation of operation of the establishment or undertaking unless the closing is for the purpose of circumventing the provisions of this Title, by serving a written notice on the workers and the Ministry of Labor and Employment at least one (1) month before the intended date thereof. In case of termination due to the installation of labor-saving devices or redundancy, the worker affected thereby shall be entitled to a separation pay equivalent to at least his one (1) month pay or to at least one (1) month pay for every year of service, whichever is higher. In case of retrenchment to prevent losses and in cases of closures or cessation of operations of establishment or undertaking not due to serious business losses or financial reverses, the separation pay shall be equivalent to one (1) month pay or at least one-half (1/2) month pay for every year of service, whichever is higher. A fraction of at least six (6) months shall be considered one (1) whole year.
Labor Code, Article 283 — Closure And Personnel Reduction. Read the full provision →
The notice is part of how the article authorizes this kind of termination
Article 283 allows an employer to terminate employment for causes such as the installation of labor-saving devices, redundancy, retrenchment to prevent losses, or closure of the establishment, but it frames that authority together with a procedural step: serving a written notice on the workers and the Ministry of Labor and Employment at least one (1) month before the intended date of termination. The one-month notice is written into the same sentence that grants the employer the power to terminate for these reasons, not tacked on as an afterthought.
Separation pay is a separate entitlement, unaffected by the notice
Whatever happens with the notice, Article 283 fixes separation pay according to the cause. For termination due to labor-saving devices or redundancy, the worker is entitled to at least one month's pay, or one month's pay for every year of service, whichever is higher. For retrenchment to prevent losses, or closure not due to serious business losses, the worker is entitled to one month's pay or at least half a month's pay for every year of service, whichever is higher, with a fraction of at least six months counted as one whole year. This entitlement does not depend on whether the notice was properly served.
What the text does not spell out
Article 283 does not itself state a specific consequence, such as a fixed damages amount, for an employer that skips or shortens the one-month notice. It establishes the notice as part of the conditions attached to this ground for termination, and it fixes separation pay by formula, but it leaves unaddressed exactly what remedy follows when the notice step is not observed. This page will not invent a figure or a rule the article does not state.
What is clear from the article regardless
Even without a stated penalty for a missed notice, the text is clear that closure or redundancy under Article 283 comes with two distinct obligations running in your favor: the one-month advance notice to both you and the labor authorities, and the separation pay computed under the applicable formula. Both exist independently of each other in the article's own wording, and neither is optional for the employer to observe.