Short answer. Not by itself. Article 178 of the Revised Penal Code punishes publicly using a fictitious name only when the purpose is concealing a crime, evading the execution of a judgment, or causing damage. A pen name, a screen name or a stage name used for no such purpose is not this offence.
What the law says
shall be imposed upon any person who shall publicly use a fictitious name for the purpose of concealing a crime, evading the execution of a judgment or causing damage
Revised Penal Code, Article 178 — Using A Fictitious Name. Read the full provision →
What the law says
Any person who conceals his true name and other personal circumstances shall be punished by arresto menor or a fine not to exceed Forty thousand pesos (₱40,000).
Revised Penal Code, Article 178 — Using A Fictitious Name. Read the full provision →
Purpose is what makes it criminal
The article lists three purposes and no others: concealing a crime, evading the execution of a judgment, and causing damage. Take those away and using another name is not punished here. Writers publishing under a pseudonym, performers with stage names, streamers with handles and people known in their community by a nickname are not committing this offence. The use must also be public — a private joke or a name used within one household does not fit. The third purpose, causing damage, is the widest of the three, and it is where most real cases live: a false name used to open an account, sign a document, mislead a victim or escape an obligation.
The lighter second paragraph
The article has a second, milder offence: concealing one's true name and other personal circumstances. This is not the same as adopting a false identity. It punishes hiding who you are, and it carries only arresto menor or a fine not exceeding forty thousand pesos. In practice it surfaces when a person refuses to identify himself, or gives a false one, in a setting where identity is expected to be disclosed. The gap between the two paragraphs is deliberate: fabricating an identity to hide a crime or hurt somebody is treated far more seriously than simply keeping your name to yourself.
Penalties, and where the figures come from
The first offence carries arresto mayor and a fine that may not exceed one hundred thousand pesos; the second carries arresto menor or a fine up to forty thousand pesos. Both ceilings are the amounts fixed by Republic Act No. 10951 (2017), which revised the fines throughout the Revised Penal Code. Many reproductions of the Code still show the original 1930 figures, which are much lower and no longer in force; if a source quotes you something different for this article, check its date. Bear in mind that the fine is a ceiling, not a fixed amount — courts set the figure within it.
What usually comes with the charge
This article is rarely the whole story. A false name used to sign a document points to falsification; used to obtain money it points to estafa; used online it may engage the cybercrime law and, where personal information of a real person was appropriated, the data privacy legislation. Using another living person's actual name is a different problem again from inventing one, because a real person is harmed. If you are being investigated, the productive question is what purpose the prosecution can actually prove, since without one of the three listed purposes the first paragraph does not apply. No outcome can be promised. Take advice before giving any statement about why you used the name.