Millions of Used Cars May Have Fake Mileage, New Carfax Data Shows

New Carfax data shows 2.45 million used cars may have rolled-back mileage. Learn how odometer fraud is rising and what buyers should check.

The U.S. used car market is facing a renewed surge of an old problem: vehicles being sold with manipulated odometer readings. According to Carfax, around 2.45 million vehicles currently on American roads may have rolled-back mileage. What stands out is not only the scale, but the pace of growth — suspected cases rose by 14% year over year, compared with a 4% increase the year before.

Digital odometers, once expected to curb mileage fraud, have not eliminated the practice. Instead, the methods have evolved. Electronic tools capable of altering mileage data have become more accessible, making manipulation less visible at first glance. At the same time, expanded data tracking and vehicle history records are increasingly exposing inconsistencies after vehicles change hands.

The financial impact on buyers is significant. Cars flagged for potential odometer rollback lose an average of about $3,300 in value. Those losses often resurface later through unexpected repairs, accelerated wear, or safety issues that do not align with the mileage shown on the dashboard.

In several states, the problem is growing faster than the national average. Montana has seen a 33% increase in suspected cases, followed by Tennessee at 30% and Arkansas at 28%. These regional spikes suggest that mileage fraud is unevenly distributed and may be influenced by local resale dynamics.

Carfax and federal regulators continue to classify odometer fraud as a federal offense, with annual consumer losses estimated at over $1 billion. Despite existing penalties, responsibility still largely falls on buyers. Reviewing vehicle history reports, checking mileage consistency across titles, service records, and insurance data remains the most reliable way to detect manipulation.

As suspected cases continue to rise, the role of transparent databases and cross-checked records is expected to become even more critical. Digital systems have not ended odometer fraud, but they are increasingly shifting the fight from mechanical inspection to data verification.