Time is running out for motorists to pay off their toll debt in Maryland under a newly enacted state law aimed at cracking down on chronic toll cheats.

The new law applies to motorists who travel through E-ZPass lanes without an E-ZPass transponder and then ignore the “notice of toll due” that arrives later by mail.

The Maryland Transportation Authority plans to mail notices in the next several weeks telling vehicle owners that they must pay off any unpaid tolls incurred before June 30. Those who pay right away can avoid the $25 administrative fee previously attached to each unpaid toll, authority officials said Wednesday.

Those who still don’t pay will receive another notice after Oct. 1, officials said. Vehicle owners who ignore the new notice for more than 30 days will then face a $50 citation per unpaid toll.

People who don’t appeal to the state’s District Court or pay the tolls and citations within 30 days will have their vehicle registration flagged for non-renewal, authority officials said.

Vehicle owners with more than $1,000 in outstanding tolls and penalties will have their vehicle registration suspended, officials said. That would allow police to pull over the vehicle at any time and seize the tag, officials said.

Maryland officials have not pursued vehicle registrations of toll scofflaws for several years because of limitations in the state’s previous tolling law. The new law took effect July 1.

As of late last year, nearly 650,000 vehicle owners owed $6.7 million in unpaid tolls dating back five years, The Post found.

The Post also found that nearly one in three motorists who used the Intercounty Connector — the state’s first all-electronic toll road — without an E-ZPass transponder never paid the toll  by mail.

Bruce Gartner, the authority’s acting executive secretary, said the new law is designed to make toll collections more fair for people who do pay.

Gartner’s advice to Maryland’s toll scofflaws: “Pay attention to your mail.”