California Cracks Down on Montana Vehicle Tax Loophole

The California Department of Tax and Fee Administration (CDTFA), together with the California Department of Motor Vehicles (DMV), has intensified enforcement efforts against the so-called Montana Loophole” The CDTFA is determined to stop the buyers of luxury or high-value vehicles from exploiting this scheme and avoiding paying California sales or use tax by registering their vehicles in Montana through shell companies, even though the vehicles are primarily used in California.

Enforcement Measures to Close the Loophole

What is now known as the Montana Loophole was originally intended to facilitate interstate commerce by allowing tax-free treatment for legitimate out-of-state vehicle purchases. However, in practice, it created strong incentives for abuse. The system requires proof that a vehicle was delivered and used outside the buyer’s home state, which unintentionally encouraged the creation of artificial documentation to simulate compliance.

To ensure that they benefit from this rule, entity formation services set up companies in low- or no-sales-tax jurisdictions such as Montana, transport companies generate paperwork indicating out-of-state delivery, and storage facilities temporarily hold vehicles to reinforce the illusion that the legal requirements have been met. The scheme masks the reality that the vehicles are primarily used in California.

To end this practice, estimated to cost more than USD 10 million in tax revenue annually, CDTFA, in cooperation with other California authorities, is deploying audits, criminal prosecutions, and technologies such as license plate readers to detect vehicles registered out of state but regularly operated locally. 

The stricter enforcement started in 2024, when CDTFA issued a warning letter to California auto dealers, cautioning that they could be liable for taxes if they fail to keep proper shipping and delivery documents. Now, with the cooperation with DMV, which provides detailed vehicle sales reports, CDTFA can identify and investigate dealerships that are assisting customers in falsely registering vehicles out of state. Notably, those who use the loophole may potentially face substantial financial penalties, including 50% of the tax on the purchase price.

Conclusion

The CDTFA is taking a step forward to combat those who buy and register luxury cars and RVs through a Montana-based limited liability company to avoid paying sales tax and higher registration fees. Notably, the existing issue highlights a significant weakness of the system: relying on USD 200 worth of documentation cannot ensure compliance. Instead of chasing paperwork, California may start applying the tax rules that focus on primary use or base location.

Source: California Department of Tax and Fee Administration