Pennsylvania Form DL-3731: Ignition Interlock License Application Steps

Pennsylvania Form DL-3731 is the one-page PennDOT application you file to get an Ignition Interlock License or, after your interlock period is over, to return to your previous license classification. It costs $42.50, or $48.50 with a motorcycle endorsement, and gets mailed to PennDOT’s Bureau of Driver Licensing in Harrisburg. Which P.O. Box you send it to depends on which of the three option boxes you check.¹

When You Use the DL-3731

There are two moments in the interlock process when this form comes into play.

The first is at the start: after a DUI conviction under 75 Pa.C.S. § 3802 or a suspension for refusing chemical testing under § 1547, you file the DL-3731 to apply for an Ignition Interlock License. That restricted license lets you drive during your suspension, but only in vehicles equipped with an approved interlock device that requires a breath sample before the engine will start and at intervals while you drive.²

The second is at the end: once you’ve completed your interlock period and your vendor has certified you had no violations in the final two consecutive months (or 30 days for ARD suspensions), you file the same form again with Option 3 checked to get your unrestricted license back.³

When You Can File

You can’t submit the DL-3731 the day your suspension starts. PennDOT sends a Restoration Requirements Letter about 30 days before you’re eligible, along with a list of approved interlock providers and the application itself.⁴

Eligibility timing depends on the offense:

First offense at any BAC tier, minor driver, school or CDL vehicle, controlled substance, or first refusal for general impairment: eligible immediately upon notice of suspension.⁵
Second offense, general impairment or chemical testing refusal: after serving 6 months of the suspension.⁵
Second offense, high or highest BAC: after 6 to 9 months, depending on the BAC tier.⁵
Third or subsequent offense: after 6 to 9 months, depending on offense type.⁵
ARD suspension: eligible immediately, and applying for the interlock license is optional.⁵

PennDOT will not issue an interlock license to someone who has never been licensed, whose license has been recalled or canceled, or who has an unsatisfied judgment from a motor vehicle accident. The interlock license also covers non-commercial driving only.

How to Fill Out the Form

Use the current version, revised July 2025. You can download it from PennDOT’s website or use the copy that arrived with your Restoration Requirements Letter.⁴

Section A: Your Information

Fill in your driver’s license number, full legal name, date of birth, phone number, and email address. Section 1510(a) of the Vehicle Code requires height and eye color as well, so complete those from the printed options on the form. If your address has changed since your last license was issued, use the address-change fields in the same section.¹

Section B: Pick One Option

Section B asks you to check exactly one of three boxes. Checking the wrong box, or checking more than one, will delay processing.

Option 1 is the standard application for an Ignition Interlock License. You’re asking for a restricted license limiting you to vehicles with an approved interlock device installed.¹
Option 2 applies if your commercial driving privilege was disqualified under Section 1617 of the Vehicle Code and you want a non-commercial class interlock license instead.¹
Option 3 is for the end of your interlock period, when you want your previous license classification back. This option includes an additional question asking whether you were cited for driving without an interlock or for tampering during your restricted period. You must answer it, or PennDOT will hold up processing.¹

Signature and Optional Items

Sign and date the form at the bottom. Two optional checkboxes let you add a $3.00 contribution to the Organ Donation Awareness Trust Fund and a $5.00 contribution to the Veterans’ Trust Fund; if you check either, PennDOT adds the amount to your payment. There’s also a veterans designation request and a photo exemption section for applicants absent due to military service, school, work, or travel.¹

The DL-3731 itself does not contain vehicle information fields or a vendor certification section. Those steps happen separately through your interlock provider and other PennDOT forms.

Fee and Where to Mail It

Include a check or money order payable to “PennDOT” for $42.50, or $48.50 if your license includes a motorcycle endorsement. Add any optional trust-fund contributions to that total. The mailing address depends on which option you selected:¹

Option 1 or Option 2: Department of Transportation, Bureau of Driver Licensing, P.O. Box 68693, Harrisburg, PA 17106-8693.
Option 3: Department of Transportation, Bureau of Driver Licensing, P.O. Box 68273, Harrisburg, PA 17106-8273.

The two P.O. Boxes look nearly identical. Check the last four digits against the option you selected before sealing the envelope. Use a tracked mailing method and keep a photocopy of the completed form and payment.

After You Submit

PennDOT reviews your application against your driving record. If you’ve met all restoration requirements, the department issues the Ignition Interlock License for Options 1 and 2, or a restoration letter returning your previous classification for Option 3. If PennDOT finds errors or missing information, they’ll contact you before processing continues.

Receiving the interlock license under Options 1 or 2 does not mean you can start driving right away. You still need an approved device installed in every vehicle you own or operate.³ Your vendor handles installation and notifies PennDOT directly. If you don’t own or operate any vehicles, you certify that separately on PennDOT form DL-21SC. Falsely claiming you own no vehicles is a third-degree misdemeanor carrying up to $2,500 in fines and a year in jail.

Filing Option 3 to End Your Interlock Period

One year after PennDOT issues your interlock-restricted license, you become eligible for an unrestricted replacement, provided you’ve had no violations.³ Two things need to happen before PennDOT will act:

Your interlock vendor submits a Declaration of Compliance certifying that during the final two consecutive months of your restricted period (or 30 days for ARD suspensions) you had no failed breath tests above.08 that weren’t corrected within 10 minutes, no missed or failed rolling retests, and no skipped calibration or maintenance appointments.³
You file the DL-3731 with Option 3 checked, answer the interlock-violation question, include the $42.50 fee, and mail it to P.O. Box 68273 in Harrisburg.¹

Do not remove the interlock device from your vehicle before PennDOT processes your application and issues your unrestricted license. Driving without the device while your restricted license is still active is a separate criminal offense.

1
Pennsylvania Department of Transportation. DL-3731 Application for Ignition Interlock License/Return
2
Commonwealth of Pennsylvania. Ignition Interlock Limited License
3
Pennsylvania General Assembly. Pennsylvania Code 75 – Ignition Interlock
4
Pennsylvania Department of Transportation. Ignition Interlock FAQs
5
Pennsylvania Department of Transportation. Ignition Interlock Limited License Eligibility Fact Sheet