Short answer. Yes. Under Article 294 of the Revised Penal Code, robbery becomes robbery with homicide when, by reason or on occasion of the robbery, a killing occurs — even if the death was not planned. It is enough that the homicide happened in the course of, or because of, the robbery.
What the law says
when by reason or on occasion of the robbery, the crime of homicide shall have been committed
Revised Penal Code, Article 294 — Robbery With Violence Against Or Intimidation Of Persons. Read the full provision →
What the law says
The penalty of reclusion perpetua to death
Revised Penal Code, Article 294 — Robbery With Violence Against Or Intimidation Of Persons. Read the full provision →
The killing need not be planned
Article 294 answers your question directly. It imposes its gravest penalty when by reason or on occasion of the robbery, the crime of homicide shall have been committed. The phrase "by reason or on occasion of the robbery" is what matters: the law does not ask whether the offender set out to kill. If a death results because of the robbery or on the occasion of it — during its commission, in the offenders' flight, or to overcome resistance — the crime is robbery with homicide, even where the killing was unplanned or committed by only one of several robbers.
It is one indivisible special complex crime
Robbery with homicide is treated as a single, special complex crime, not two separate offenses. What binds them is the connection between the taking and the killing: the homicide must be linked to the robbery, which remains the offenders' main purpose. Because it is one crime, the penalty is fixed by Article 294 for the combination, rather than adding a separate homicide penalty. This is also why the label uses "homicide" in a generic sense — it covers the killing that accompanies the robbery, regardless of how many died, as long as the deaths are tied to the robbery.
The penalty, read subject to later law
For robbery with homicide, paragraph 1 sets the penalty at The penalty of reclusion perpetua to death. Two later laws must be read alongside this. Republic Act No. 7659 (1993) is the source of the amended text of this article. And Republic Act No. 9346 (2006) prohibits the imposition of the death penalty in the Philippines; where the Code's nomenclature is used, reclusión perpetua is imposed in its place. So while the article still prints "to death," that maximum can no longer actually be imposed, and reclusión perpetua stands as the penalty in practice.
What must still be proven
The doctrine is strict, but it is not automatic. The prosecution must still prove a genuine robbery — an unlawful taking of property with violence or intimidation — and that the killing was connected to it, not an entirely separate matter that merely happened nearby. If the taking of property was an afterthought to a killing, or the two are unrelated, the special complex crime may not apply, and the acts may be judged as distinct offenses instead. The link between the robbery and the death, rather than any plan to kill, is the decisive question.