Signing someone else’s name to a document, even with seemingly good intentions, can carry serious criminal consequences in Pennsylvania. Yes, it is illegal to forge a signature on a document in Pennsylvania. State law makes forgery a crime whenever a person acts with intent to defraud or injure another, and the severity of the charge depends heavily on the type of document involved.
The Statute: 18 Pa.C.S. ยง 4101
Pennsylvania’s forgery law is codified at Title 18, Section 4101 of the Pennsylvania Consolidated Statutes. Under this statute, a person is guilty of forgery if, with intent to defraud or injure anyone, or with knowledge that they are facilitating a fraud or injury to be perpetrated by someone else, they alter any writing of another without authority, or make, complete, execute, authenticate, issue, or transfer a writing so that it falsely appears to be genuine. The statute defines “writing” extremely broadly, covering not just traditional paper documents but also printing, credit cards, badges, trademarks, electronic signatures, and other symbols of value, right, privilege, or identification.

Why Intent Matters So Much
The critical element separating forgery from an innocent mistake is intent to defraud or injure. Pennsylvania law does not criminalize every instance of signing someone else’s name; it specifically requires that the person acted with the purpose of deceiving someone or causing harm through that deception. If a person had actual permission to sign on another individual’s behalf, forgery generally does not apply, since the required lack of authorization and fraudulent intent would be missing. That said, this permission can be difficult to prove after the fact if the person who gave it later denies doing so, which means even authorized signing carries some practical legal risk if a dispute arises later.
How the Type of Document Affects Grading
One of the more distinctive features of Pennsylvania’s forgery statute is that the severity of the charge depends heavily on what kind of document was forged, rather than on a single uniform penalty. Forgery is graded as a second-degree felony if the writing is, or purports to be, part of an issue of government-issued money, securities, postage or revenue stamps, or an issue of stock, bonds, or other instruments representing an interest in or claim against property. Forgery is graded as a third-degree felony if the writing is, or purports to be, a will, deed, contract, release, commercial instrument, or other document that creates, transfers, alters, terminates, or otherwise affects legal relations. Any other type of forged writing falling outside these two categories is graded as a first-degree misdemeanor.
Common Real-World Examples
This tiered grading structure means forgery charges can look very different depending on the document involved. Forging a signature on a will or a real estate deed, documents that directly affect legal rights and relationships, exposes a person to third-degree felony charges. Signing someone else’s name on a personal check or credit card slip without authorization can similarly implicate the statute, given how broadly “writing” is defined to include financial instruments. Even seemingly minor situations, like signing a friend’s name on a delivery receipt or a form without their knowledge, could theoretically fall within the statute’s misdemeanor catch-all provision if fraudulent intent were present.
Penalties for a Conviction
Given the graded structure of Pennsylvania’s forgery law, penalties vary substantially. A second-degree felony conviction can carry up to ten years in prison and significant fines, a third-degree felony conviction up to seven years, and a first-degree misdemeanor up to five years. Beyond the criminal sentence itself, a forgery conviction results in a permanent criminal record that can affect employment, professional licensing, and other future opportunities.
Bottom Line
Forging a signature in Pennsylvania is a serious offense whose consequences hinge heavily on the type of document involved and whether fraudulent intent can be proven. Anyone facing a forgery charge, or unsure whether a specific signing situation might expose them to liability, should consult a licensed Pennsylvania criminal defense attorney.
