This feels like a mistake. I checked; it's not. If you have an old phone you're looking to retire in favor of a shiny new 5G-capable model, here's an insanely affordable option: For a limited time, you can get the Motorola One 5G Ace for $20 when you port an existing number to Metro by T-Mobile. List price: $400. Regular price at Metro: $280. (Update: A previous deal had the phone for just $20, but $30 is still an amazing buy.)

There's a catch, but probably not what you think: You don't have to sign any kind of contract, nor are you roped into Metro's most expensive service plans. (Over at Cricket, for example, you can get an iPhone SE for $50, but you have to pay for two months of service on a plan costing at least $60 a month.) You do, however, have to visit a brick-and-mortar Metro store; you can't order the phone online. 

Also, the number you're porting in can't be from T-Mobile. And if you've been a Metro customer anytime in the last six months, you're not eligible for this deal.  

Metro's plans start at $40 a month for a single line, with discounts available as you add lines. The phone itself will cost you $30 (plus tax and a $20 activation fee) out the door -- effectively a $250 instant rebate.

If you've never heard of this model, that's because it's brand-new; it was one of four new under-$400 phones Motorola introduced last month. CNET's Patrick Holland had this to say in his Motorola One 5G Ace review: "The Motorola One 5G Ace is a good $400 phone, a great $300 phone and an absolutely fantastic $20 phone." (Again, that refers to an earlier promotional price.)

Indeed, there's some pretty decent horsepower here for a $400 phone, let alone a $30 one: a 6.7-inch HDR10 display, a Snapdragon 750G 5G processor, 6GB of RAM, three rear cameras.

According to a Metro representative, the phone is sold locked but can be unlocked after six months of paid service.

Your thoughts?

Read more: Best phones under $500: iPhone SE, Pixel 4A 5G, Galaxy A51 and more

Originally published last month. Updated with a new deal.

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