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Best Used Samsung Galaxy S21 Deals Today

AI-curated top picks from hundreds of eBay listings. Updated daily with verified sellers and transparent pricing.

Top Picks Today

Updated: Apr 24, 2026

Product Image Samsung Galaxy S21 SM-G991U 128gb Gray Verizon Small Dot
#1

Samsung Galaxy S21 SM-G991U 128gb Gray Verizon Small Dot

Used

$79.99
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Why we picked it #1

If you're looking for the absolute lowest price, this Galaxy S21 catches your eye. For $79.99, you get the same core features as every other S21 here: a fast processor, vibrant display, solid cameras, and 128GB of storage. Two honest tradeoffs: this phone is locked to Verizon, so you won't be able to use it on other networks, and there’s a small black dot near the bottom left—purely cosmetic, but still something you’ll notice in certain lighting. If you don’t mind being tied to Verizon and are comfortable with a used device that has a visible mark, you’re getting one of the cheapest tickets into a still-capable Samsung flagship. Compared to others in the lineup, especially the pricier unlocked refurbished models, you’re sacrificing flexibility and condition, but the savings might be worth it if those things don’t matter as much to you.

Product Image Samsung Galaxy S21 5G SM-G991U1 (White 128GB 8GB) Unlocked SingleSIM SCRATCHD
#2

Samsung Galaxy S21 5G SM-G991U1 (White 128GB 8GB) Unlocked SingleSIM SCRATCHD

Used

$93.00
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Why we picked it #2

This listing gets you a fully unlocked S21 for a low price—but with a few catches. You’re saving compared to most of the lineup, and being unlocked means you have freedom to swap to almost any carrier. The tradeoff? There are quite a few physical imperfections: lots of scratches and some residue on the screen, and much more concerning, the rear camera lens is missing. That could impact camera use, dust protection, and overall device durability. If having a phone that works on any network is critical for you and you’re comfortable with wear or planning to use a case, this could work—but if you care about camera performance or want a device that looks clean, one of the refurbished options further down might be better suited, even for a bit more money.

Product Image Samsung Galaxy S21 S991U 5G SM- G991U1 - 128GB - FACTORY UNLOCKED - EXCELLENT
#3

Samsung Galaxy S21 S991U 5G SM- G991U1 - 128GB - FACTORY UNLOCKED - EXCELLENT

Excellent - Refurbished

$159.48
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Why we picked it #3

This listing sets itself apart with peace of mind and care: the phone is refurbished to an excellent standard, includes an authentic Samsung charger, comes with a free screen protector, and is backed by a 30-day hassle-free return policy. Plus, it’s been tested by certified techs, and you’ll get personal customer support if any issues crop up. You’re paying nearly twice as much as the cheapest options here, but for that jump, you’re avoiding unknowns—no network lock, no mystery scratches, no missing camera parts. If you value getting a device that will look and feel almost new, want quick shipping, and desire a smoother buying process, this is a strong pick. If budget is your top concern, it’s a stretch, but you’re paying for assurance and condition, which the cheaper options lack.

Product Image Samsung Galaxy S21 5G SM-G991U 128GB Unlocked Smartphone - Image Burn
#4

Samsung Galaxy S21 5G SM-G991U 128GB Unlocked Smartphone - Image Burn

Used

$104.99
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Why we picked it #4

This one’s an unlocked Galaxy S21 at a mid-range price, but there’s a major flag: the listing notes image burn-in on the display. That means you might see permanent ghosting or outlines on your screen—which will always be visible, especially on bright backgrounds. It’s a step up from the very cheapest because you get unlocking flexibility, but for just a little more, you could find options that don’t have burn-in or have better cosmetic condition. If your plan is to use this as a backup or secondary phone, you might not mind the flaw. Otherwise, consider paying a bit more for one of the refurbished units without screen issues, as that makes a big difference for daily use.

Product Image Samsung Galaxy S21 5G 128GB G991U Unlocked - Good
#5

Samsung Galaxy S21 5G 128GB G991U Unlocked - Good

Good - Refurbished

$133.99
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Why we picked it #5

This pick strikes a balance—moderate price, refurbished condition, and an unlocked handset with a third-party charger included. The big plus is you’re not tied to a single carrier, and you’re likely getting a phone that’s been checked over, so fewer surprises. The not-so-great news: the phone has some noticeable scratches and dents, and battery health clocks in at 82%, which is below new. If you don’t mind minor wear, you’ll save money compared to the ultra-clean refurb options and dodge the big issues like screen burn or missing parts that some cheaper listings have. You won’t get original packaging, but this is a solid value if you want a working S21 for less, just keep your expectations realistic around looks and battery life.

Product Image Samsung Galaxy S21 5G 128GB G991U Unlocked - Very Good
#6

Samsung Galaxy S21 5G 128GB G991U Unlocked - Very Good

Very Good - Refurbished

$147.99
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Why we picked it #6

You’re getting a "Very Good" refurbished Galaxy S21 here, which means fewer cosmetic issues than most used options and a phone that’s ready to work on any carrier. The price is in the mid-to-upper range, so you pay more than the real bargains, but that comes with the expectation of a cleaner device—though some scratches or minor nicks may still be present. The seller’s strong reputation (lots of positive feedback) adds extra reassurance. If you want an unlocked device that won’t surprise you with major defects but aren’t picky about tiny signs of prior use, this finds a nice middle ground between the cheapest phones (with their bigger flaws) and the top-priced "excellent" options.

Product Image Samsung Galaxy S21 5G SM-G991U 128GB 256GB Unlocked Very Good Refurbished
#7

Samsung Galaxy S21 5G SM-G991U 128GB 256GB Unlocked Very Good Refurbished

Very Good - Refurbished

$137.99
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Why we picked it #7

This listing lands you a “Very Good” refurbished S21 at a fair price, with some standout perks. A full year of Allstate warranty and a 30-day free return window give you more protection than most others here. It’s fully unlocked—so you can use it just about anywhere—and while it’s not pristine, “Very Good” means only light signs of prior use. The main compromise? Battery health is down at 80%, so you’ll notice slightly quicker power drain compared to a new device. You’re getting only the phone and charging cable (no original box or extras), but if you want a balance between price, condition, and solid after-sale support, this is a compelling option—especially if a bit of cosmetic wear and reduced battery stamina don’t bother you.

Product Image Samsung Galaxy S21 5G 128GB G991U Unlocked - Excellent
#8

Samsung Galaxy S21 5G 128GB G991U Unlocked - Excellent

Excellent - Refurbished

$161.99
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Why we picked it #8

This is one of the top-condition phones in the lineup: excellent, refurbished, and unlocked. It includes a third-party charger and comes with free shipping anywhere in the US. You’ll pay noticeably more here than for most other options, and the warranty won’t cover you if you’re outside the US, but you are getting a phone that should look and feel almost new. There’s no original packaging, so don’t expect it to feel like buying retail. If having your S21 look spotless out of the box matters most to you—and you want the reassurance that comes with a top-tier refurb—this is a strong, if pricier, pick. If you’re working with a tighter budget, you can save by considering the "Very Good" or "Good" refurb options instead.

Product Image Samsung Galaxy S21 5G G991U T-Mobile Unlocked Verizon Mint Straight Talk Boost A
#9

Samsung Galaxy S21 5G G991U T-Mobile Unlocked Verizon Mint Straight Talk Boost A

Excellent - Refurbished

$159.99
View on eBay

Why we picked it #9

Here’s a refurbished S21 in excellent condition with multiple carrier options, backed by a genuine Samsung charger and real-time customer support if you need help. The tradeoff is big: this phone has screen burn-in, so you’ll see some permanent marks or shadows on the display. It’s also locked to your chosen carrier (not universally unlocked), so you’ll want to make sure you pick the right one. For the price, you’ll find options above and below it that don’t have screen burn or network lock issues. Unless you’re okay with those flaws for the peace of mind that comes with excellent refurb and a top-condition appearance, you may prefer an unlocked S21 without screen issues—even if it means giving up the OEM charger or spending slightly less.

Product Image Samsung Galaxy S21 5G SM-G991U1 128GB 256GB Unlocked Good Refurbished
#10

Samsung Galaxy S21 5G SM-G991U1 128GB 256GB Unlocked Good Refurbished

Good - Refurbished

$169.95
View on eBay

Why we picked it #10

This refurb listing offers the largest storage of the bunch—256GB—so if you want to stock up on apps, photos, and videos, this is your chance. There’s also a 1-year Allstate warranty, which brings some peace of mind. However, it comes with a few notable compromises: the price is the highest of the group, it has screen burn-in (which leaves visible marks on the display), battery health is low at 80%, and you’re only getting a charging cable (no charger block or original box). Plus, this phone ships only USPS to PO Boxes. In short, you’re getting more storage, but less everywhere else: lower battery life, some screen defects, and a higher price. If 256GB of space is a must-have and you’re okay with those tradeoffs, this is for you—but for most, an excellent refurb with fewer flaws (and less storage) could feel like a smarter buy.

Our AI Expert Finds the Best Samsung Galaxy S21 Deals, Every Day

Every day, our AI analyzes hundreds of Samsung Galaxy S21 listings across major resellers to surface the truly best deals — not just the cheapest.

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