Update July 24th, 2019, 2:20PM ET: This article has been updated to include additional information about which cars are eligible for Amazon’s Key service.

In 2017, Amazon offered its customers the chance to get packages delivered inside their homes with its new Key service. What if you’re nervous about giving Amazon the right to open your front door, but you’re also tired of having your purchases left out in the rain? Well, in 2018, Amazon offered an alternative: the company will deliver your packages to the trunk of your car where it can sit in relative security.

The service is available for specific models of premium cars (most recently, cars from Honda and Acura) in specific cities. Your car must also have an active, eligible connected car service plan such as OnStar, On Call, or a plan specific to the manufacturer. Keep in mind that these connected car plans are not inexpensive; for example, HondaLink Remote costs $110 / year after a three-month trial. However, if your vehicle does qualify, there aren’t any add-on costs for using Amazon Key.

If you want to give it a try, here are the current requirements:

• You must be a Prime member
• You must live in one of the supported cities
• You must have one of the following eligible vehicles:

Buick, Cadillac, Chevrolet, GMC, and Volvo models from 2015 or later with an active connected car service plan (such as OnStar)

Ford 2017 or later vehicles equipped with FordPass Connect

Lincoln 2018 or later vehicles (except MKT) equipped with Lincoln Connect

Honda 2018 or later (Accord Touring, Odyssey Touring/Elite) or 2019 or later (Insight Touring, Passport Touring/Elite, Pilot Touring/Elite) vehicles equipped with HondaLink Remote

Acura RDX 2019 or later vehicles equipped with AcuraLink Remote

(For more information, Amazon offers a detailed list of eligible vehicles and connected car service plans.)

• Finally, your package must not: weigh over 50 pounds, be larger than 26 x 21 x 16 inches, require a signature, or come from a third-party seller

Got it? If you have the right type of car, live in the right area, are a Prime member, and fit all the other criteria, then you can begin getting deliveries to your car.

To get started, the first step is to sign up for Amazon Key:

• Go to the Amazon Key page, the Apple App Store, or the Google Play Store, and download and install the app
• Start the app and select “Set Up Vehicle” 
• The next screen will let you check if your vehicle and location are eligible (assuming you haven’t already)
• After several screens explaining how the car delivery works, you will be asked to enter information about your vehicle. You can then link your vehicle’s connected car service plan to your Amazon account.

That’s it! After this, when you purchase something through Amazon and choose an address that’s eligible for in-car delivery, you will be presented with that option, along with a delivery window for same-day or second-day delivery.

A couple of other items to be aware of:

• You have to park within two blocks of your delivery address in a publicly accessible place. (The Key app will show you if you’re within range.)
• If you change your mind or park outside the eligible range, the deliverer will either, according to Amazon, drop the package off at the indicated address or try again the next day

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