You can now upgrade your next Amtrak trip with new bidding system, but is it worth it?

There's an exciting new way to upgrade on Amtrak today. The passenger rail company confirmed to TPG that it is offering customers the option to upgrade to business or first class via paid bidding. There's a chance it could eventually be possible to upgrade to a sleeper car and/or a bunk.

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Amtrak's new "BidUp" system allows customers to bid on upgrades with cash. Right now, unfortunately, you can't use your Amtrak Rewards points.

According to Amtrak, "Customers with existing reservations can visit Amtrak.com/BidUp, check eligibility up to two hours prior to departure and place a bid to upgrade their reservation into our premium classes of service: business class (most corridor routes) and first class (Acela)."

Rail passengers only get billed if their bid is accepted. There is no fee for bidding.

In a press release, Amtrak Executive Vice President and Chief Marketing and Revenue Officer Roger Harris said, “BidUp is a great way for more Amtrak customers to enjoy our premium services."

So, what do you get when you are upgraded?

Related: Acela business class review

Related: Acela first class review

Business-class customers get dedicated cars or sections on the train with more legroom and reserved seating on the Northeast Regional, Palmetto, Carolinian and Vermonter train lines. They also get 25% bonus points.

First-class riders get access to reserved seating in the first-class cabin (could be great for the Boston-New York-Washington Acela line). They also receive complimentary meals, beverages, lounge access and a 50% points bonus.

Is it worth it? Travel industry analyst and rail fan Jamie Larounis says, "The upgrade offers aren't a great deal."

I spoke to Larounis after he had posted a few of his offers on Twitter. He told me that, for the most part, the deals weren't great because the hard product and service on first and business class on most routes weren't worth spending much extra for. He said:

"The best upgrade scenario in the Northeast would be from Acela Express Business Class to First Class, where there are fewer seats, at-seat food and beverage service, and lounge access in major stations — still, this upgrade would only be worth it on the lower end of the range Amtrak is accepting bids for (the “poor” range)."

Related: Amtrak plans to expand new nonstop Acela service from New York

Still, some folks won't mind paying a small upgrade fee for those kinds of perks. Extra legroom is worth at least $15 to me, even on a short trip.

Amtrak says, "Bidding for an upgrade to a private room will be offered at a later date." In other words, you can't yet bid for a bed or private bunk on any of Amtrak's longer routes.

Related: Your ultimate guide to Amtrak Guest Rewards

Larounis told me that is where the real value could eventually lie: "There could be value on longer routes where there are sleeping car accommodations, though if you’re wanting a bed, you’re likely to purchase this at booking instead of hoping for space to still be available for bid. With sleeper accommodations, this is where you’re likely to get the most value out of any train Amtrak operates — simply because of the privacy and flat-bed offering that is important on daylong or more train rides."

Related: The brand new high-speed Acela cars

Let's hoping that's the next iteration of this interesting new feature.