South Carolina Ignition Interlock — Requirements & Costs
When interlock may be required and practical steps.
When South Carolina requires an IID §56-5-2990
mandatory for all DUI convictions including first offense, regardless of BAC level (as of May 19, 2024 'All Offender Law').
How long the IID must remain installed
6 months (first offense after suspension); 2 years (second); 3 years (third; 4 years if within 5 years of first); lifetime (fourth or subsequent).
How the device works in practice
Violations and extensions
Common violations that can extend the IID period or trigger additional consequences:
- Failed startup tests (BAC above threshold)
- Failed rolling retests
- Missed calibration appointments
- Tampering with or attempting to circumvent the device
- Operating a vehicle without an IID when one is required
Costs
IID costs are borne by the offender and include:
- Installation fee
- Monthly monitoring/rental fee
- Removal fee
- Calibration fees (may be included in monthly rental or charged separately)
The IID as a path back to driving
While the IID is a restriction, it is also the mechanism that allows many offenders to resume driving sooner than they would under a full suspension. In South Carolina, restricted driving privileges during the suspension period are limited. Complying fully with IID requirements — no violations, on-time calibration — is the fastest path to full reinstatement.
Ready to Talk to a Lawyer?
Submit a short intake form and a participating South Carolina attorney who handles this type of matter may reach out to you. No commitment required.
Frequently Asked Questions
General answers to common questions. Specific outcomes depend on your facts and timing.
If you have a deadline, court notice, or upcoming hearing, mention it when requesting assistance so timing can be evaluated promptly.