Short answer. Generally yes. The Labor Code sets separation pay at a minimum of one month's pay regardless of years of service, so a recently hired worker is not excluded for lack of tenure. The one exception the article carves out is closure due to serious business losses, which is not covered by the amounts it prescribes.
What the law says
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.
Labor Code, Article 283 — Closure And Personnel Reduction. Read the full provision →
The formula has a floor, not just a per-year rate
Article 283 does not simply multiply a rate by years of service. For redundancy and labor-saving devices, it sets separation pay at at least his one (1) month pay or to at least one (1) month pay for every year of service, whichever is higher. For retrenchment and most closures, the formula is one (1) month pay or at least one-half (1/2) month pay for every year of service, whichever is higher. In both formulas, one month's pay is the floor — the per-year calculation only matters once it would exceed that floor.
Why length of service does not disqualify a recent hire
Because the article guarantees at least one month's pay regardless of the per-year figure, a worker with only weeks or a few months of service is not shut out simply for being new. The article also states that a fraction of at least six (6) months shall be considered one (1) whole year, which affects how partial years are counted toward the per-year rate, but it does not remove the one-month floor for anyone whose service falls short of that fraction.
The one real limit the article draws
The article's separation pay amounts for retrenchment and closure apply specifically to closures not due to serious business losses or financial reverses. Closure caused by serious business losses is not covered by that formula in the text. Whether a recently hired worker gets separation pay under this article, then, depends more on the reason for the closure than on how long the worker had been employed.
What to check first
If your company is closing, the ground given for the closure matters as much as your length of service. Redundancy and labor-saving-device terminations carry the one-month floor with no carve-out for business losses. Closures and retrenchment carry the same floor, but only where the closure is not attributed to serious business losses or financial reverses. Your date of hire and the date the notice takes effect are the two figures the computation turns on, so check both against your contract and payslips before accepting any offered amount.