In an effort to clear out the last of its inventory, General Motors has added the Chevrolet Volt to its list of models eligible for an 18 percent discount off sticker price this month.

When it went on sale in December 2010, the Volt was the first mainstream-brand plug-in car of the modern era (beating the Nissan Leaf by a matter of days.) It literally ushered in a new era of electrified transportation.

Now buyers who still haven't managed to get in on a new Chevy Volt can put a 2018 model in their garage for a big 18 percent discount off MSRP.

READ THIS: GM rolls last Chevy Volt off Detroit assembly line

On a Volt Premier, which comes with leather seats and available driver assist systems, that can amount to about $7,000 off.

The bad news is that the Volt, and its Johnny-come-lately all-electric sibling, the Chevy Bolt EV, have been just popular enough that neither car is eligible for the full $7,500 tax credit from the federal government.  As of April, the tax credit on both models was reduced to $3,750—which will be the case through September, and likely until all of Chevy's remaining Volts have been sold off.

Still, with the remaining tax credit, it's a better deal than buying a Volt earlier this year with the full tax credit and no discount.

CHECK OUT: 10 lessons from the short life of the Chevy Volt, 2011-2019

The 2019 Volt is also eligible for a $3,000 cash rebate. Buyers of 2018 Volts can opt instead for $1,000 cash back and 0 percent financing for six years on a Volt Premier.

2019 Chevrolet Volt

2019 Chevrolet Volt

The Volt went out of production in February, after GM announced its demise in November along with several other slow-selling sedans. It offers 53 miles of all-electric range, enough to accomplish what more than 90 percent of Americans do every day without burning a drop of gas. After that, its 149-horsepower, 1.5-liter gas engine kicks on to keep the juice flowing.

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Car shoppers interested in a Volt can also lease one for $319 a month for 39 months, but it requires a big $5,299 down payment. That amounts to an effective deal of $453 a month—$88 more than a Toyota Prius Prime, which also offers a compelling $309-per-month lease deal in California in May.

The deals end May 31. Selection of this discontinued car is limited, so act fast.

Correction: This story clarifies that the 18 percent discount is available on 2018 models.