Tennessee DUI Laws & Penalties
Last reviewed:
TN has mandatory jail on EVERY DUI conviction — 48 hours minimum even first offense — one of the few states with no way around initial confinement.
Overview
- Legal BAC limit: 0.08% (commercial 0.04%, under-21 0.02%, enhanced at 0.2%).
- Lookback period: 10 years. 10-year lookback for prior-offense counting (20-year outer window applies when there are already priors within 10 — verify at page QC). 4th offense = felony.
- Primary statute: T.C.A. § 55-10-401 (offense); § 55-10-402 (penalties)
0.20+ raises first-offense mandatory minimum from 48 hours to 7 consecutive days.
Penalties by offense
| Offense | Classification | Jail | Fine | License suspension | Interlock |
|---|---|---|---|---|---|
| First offense | Class A misdemeanor | 48 hours – 11 months 29 days; mandatory min 48 consecutive hours (7 days if BAC 0.20+); litter pickup alternative available in limited cases | $350–$1,500 (plus costs and towing/bail) | 1 year; hardship: restricted license available; geographic/interlock conditions | Required |
| Second offense | Class A misdemeanor | 45 consecutive days – 11 months 29 days; mandatory min 45 days | $600–$3,500 | 2 years; hardship: restricted with IID after 1 year (conditions) | Required |
| Third offense | Class A misdemeanor | 120 consecutive days – 11 months 29 days; mandatory min 120 days | $1,100–$10,000 | 6 years; hardship: restricted with IID (conditions) | Required |
| Fourth+ offense | Class E felony (4th+) | 150 consecutive days (1-year minimum sentence) – 6 years; mandatory min 150 days | $3,000–$15,000 | 8 years; hardship: narrow | Required |
First offense
- Classification: Class A misdemeanor
- Jail: 48 hours – 11 months 29 days; mandatory min 48 consecutive hours (7 days if BAC 0.20+); litter pickup alternative available in limited cases
- Fine: $350–$1,500 (plus costs and towing/bail)
- License suspension: 1 year; hardship: restricted license available; geographic/interlock conditions
- Alternative disposition: No judicial diversion for DUI; DUI school + victim impact panel standard.
- Interlock: IID required for restricted license if BAC 0.08+ (effectively most convictions); 6 months post-revocation IID standard; 0.15+ makes IID mandatory conditions stricter.
- Child under 18 in vehicle: +30 days mandatory minimum (child endangerment enhancement).
Second offense
- Classification: Class A misdemeanor
- Jail: 45 consecutive days – 11 months 29 days; mandatory min 45 days
- Fine: $600–$3,500
- License suspension: 2 years; hardship: restricted with IID after 1 year (conditions)
- Vehicle forfeiture/seizure possible on second offense.
Third offense
- Classification: Class A misdemeanor
- Jail: 120 consecutive days – 11 months 29 days; mandatory min 120 days
- Fine: $1,100–$10,000
- License suspension: 6 years; hardship: restricted with IID (conditions)
Fourth+ offense
- Classification: Class E felony (4th+)
- Jail: 150 consecutive days (1-year minimum sentence) – 6 years; mandatory min 150 days
- Fine: $3,000–$15,000
- License suspension: 8 years; hardship: narrow
- 6th+ = Class C felony — verify current ladder at page QC.
Refusing a chemical test (implied consent)
Refusal: civil violation — 1-year license revocation (2 years with prior; longer if crash/injury). Refusal admissible as evidence. Courts may order forced blood draw with warrant.
Statute: T.C.A. § 55-10-406
Ignition interlock
IID required for restricted licenses for most convictions (state pays via IID fund for indigent); 6-month post-revocation IID standard, longer with enhancements; 'restricted geographic license' era largely replaced by IID-anywhere licenses.
Statute: T.C.A. §§ 55-10-409, 55-10-417
Frequently asked questions
What is the penalty for a first DUI in Tennessee?
A first DUI in Tennessee is a Class A misdemeanor. Jail: 48 hours – 11 months 29 days; mandatory min 48 consecutive hours (7 days if BAC 0.20+); litter pickup alternative available in limited cases. Fine: $350–$1,500 (plus costs and towing/bail). License suspension: 1 year; hardship: restricted license available; geographic/interlock conditions.
What is the legal BAC limit in Tennessee?
0.08% for most drivers, 0.04% for commercial drivers, and 0.02% for drivers under 21.
How long does Tennessee look back at prior DUI offenses?
10 years. 10-year lookback for prior-offense counting (20-year outer window applies when there are already priors within 10 — verify at page QC). 4th offense = felony.