The first thing that we need to get straight here is that a charge alone of statutory rape or other sex offense will not land you in prison. You may be in jail for a short time until bond is posted, but a charge is not the same as a conviction, so the easy answer is no, a statutory rape charge does not mean a prison sentence.
A stat rape conviction however is an entirely different story. If you are convicted of any of the four types of statutory rape in North Carolina, you will be punished as a felon and should expect to spend at least a few years in prison, depending on the details surrounding the sex crime and any prior criminal history you may already have.
First, second and third degree rape convictions are punished as Class B1 felonies. This level of felony sex offense requires an active prison sentence of at least 144 months. If you receive a maximum sentence you will face life in prison without parole.
A conviction for fourth degree statutory rape is a Class C felony. This level of felony sex offense requires a minimum of 44 months in prison.
An experienced criminal defense attorney may be your best sex crimes defense option if you are facing statutory rape charges. Asserting that you were wrong about the alleged victim's age is not considered a valid defense to the crime and you can be convicted of stat rape.
Source: Ask.SuperLawyers, "How Long Will I Go To Jail For Statutory Rape In North Carolina?"