In Pennsylvania, you can receive a fine of between $200 and $1000 (the judge sets the amount) or imprisonment for up to six months, or both if you are convicted of driving without a license for a third time.
Beyond the penalties listed, above your driving privileges (though you are unlicensed) will be suspended/revoked for a period of time and you will be assigned points on a driving record that PA sets up for you.
The Commonwealth of PA says in Motor Vehicle Code (MVC) Chapter 15 that no person may drive any motor vehicle upon a highway or public property without a driver's license valid under their laws. PA law goes on to explain that public property includes, but is not limited to, driveways and parking lots owned or leased by the Commonwealth or an agency thereof.
When one is convicted of a first offense of driving without a valid license in PA, they are guilty of a summary offense and are sentenced to pay a fine of up to $200. This violation also comes with a driving record being created for you and it being assessed 3 points for a "violation concerning the license."
Under Section 6503 of the PA MVC it states that a second or subsequent conviction of being an unlicensed driver within seven (7) years of the first offense of driving without a license comes with the fine amount we listed at the top, $200 to 1000 and the possibility of going to jail for up to 6 months. If you keep driving without a license and get convicted for a sixth or subsequent time then the penalties will include a fine of at least $1,000 and imprisonment for at least 30 days but not more than six (6) months.
The Pennsylvania driver's manual notes that a second or any additional offense of driving without a valid driver's license within a 5-year period also comes with a suspension of the person's right to drive. During the suspension period you would be unable to apply for a license.
Typically someone that is under suspension or revocation would have to turn in their driver's license or driving permit but in the case of an unlicensed driver, an Acknowledgement of Suspension/Revocation (Form DL-16LC) or an affidavit acknowledging the sanction must be surrendered to PennDOT in lieu of a driver's license/learner's permit.
The Pennsylvania Department of Transportation (PennDOT) says that after your driving privilege is restored by the state (though to actually drive legally you would still need to obtain a valid driver's license); your driving record will show five (5) points.
Keep in mind that if you are unlicensed and caught driving during your suspension or revocation time then you could be cited not only for not having a driver's license but driving during a suspension period which means you would face harsher penalties yet such as more fines and a longer suspension/revocation period (1 to 2 years longer normally).
If a person is driving without a license they are likely also to be driving without insurance since to have car insurance you normally need a valid driver's license. If you are found to be an uninsured motorist in PA the penalties can include a fine as well as the suspension of the vehicle's registration and operator's driving privileges.
If you have been cited in Pennsylvania for driving without a license for a third time you should contact the court on your ticket and/or PennDOT for more information on the penalties you may be facing and determine if you need a lawyer to help you.