Customer Ratings & Reviews

Seagate Expansion 20TB External USB Hard Drive arrived in retail box, 1-Year Warranty. The power adapter included several changeable international power plug types. MicroUSB 3.0 cable plug. Fairly quiet, but does make a chugging sound. Runs hot 55C in the enclosure. Drive inside is a Seagate BarraCuda ST20000DM001-3Y3103, Made in Thailand. Actual capacity 18.19 TB free space (20,000,586,850,304 bytes). Fast speeds, Sequential 246 MB/s, 239 MB/s R/W, 7200 rpm. About the same performance as an IronWolf Pro. Ran a full surface scan, 30+ hours. No issues, works fine. Good enough for simple NAS storage.

It's a great value, especially if you can catch it on sale. Performance is good for a hard drive. It does run rather hot, over 50C, and makes disconcertingly loud clicking and clunking noises, especially when it starts up. I'm assuming this is normal for this drive model and that nothing is wrong with it until proven otherwise.

Bought two, shucked them, no pin mod needed. They're working great in my synology nas. I stress tested them both, did a secure erase followed by a full smart test and both worked fine. Opening up the enclosure was a bit of a mess. There are plastic clips on each side, in the center. Google says these might be HAMR drives, which is newer HD tech that Seagate uses and their long term reliability is kinda unknown. Time will tell. No issues with temps, they run cooler than my WD Red Plus.

20tb is alot but out the box it was at like 18.6 tb free and i tried to reformat it, thinking it would jump up to 20tb but it didnt so idk why they market it as 20tb its very loud and vibrates it could be that its 20tb and is big so its just alot more aggressive or its faulty and ill have to return doing research its supposedly normal for this size idk it isnt slow or anything so ill see but besides the tb not being at a full 20 or heck even 19tb is crazy but so far its being very useful and im only writing any of this cuz theres no reviews im sure not alot of people are in the market for 20tb haha i also bought there 14tb version which has none of the loudness mentioned above but it dis also out the box come in at 12.somthing TB

Nice sturdy external HDD, functions like it should. No issue so far.

Had 145 reallocated sectors within a couple weeks of use.

Mechanical hard drives, whether internal or external, were left in the dust by solid state drives’ speed long ago. But they still reign supreme when it comes to cost-effective mass storage, especially for backups, and it’s in this vein that this Seagate Expansion external desktop drive steps forward with its massive 20TB capacity. It’s an ideal device to serve as secondary or tertiary storage, with plenty of room even for data hoarders like me who like having a local backup in addition to, or in lieu of, cloud storage. The Seagate drive is housed in a simple black rectangular enclosure with plenty of ventilation. The outer casing does appear to be a bit of fingerprint magnet–surprising, given what you’d expect from the look of the texture–and houses at one end the micro-USB-B connector and power connector. The other end of the USB cable is a Type-A connector. The power connector came with an incredible variety of international plug options, which you slot into the power connector for connection to the wall. Out of the box, the drive is formatted as ExFAT, which ensures the broadest compatibility. But ExFAT does not do journaling, which helps protect against potential file loss/corruption when faced with sudden power outages or an accidental disconnection. Since I’m using it exclusively with Windows devices, I reformatted to take advantage of the journaling feature in the Windows NTFS file system. Using it with a Mac for Time Machine will also require a reformat as well. Formatted, I ended up with slightly over 18TB usable storage, which is as expected. While the drive does come with Seagates’s Rescue data recovery service, which promises access to professional data recovery (nice, since personally repairing damaged hard drives is generally well beyond what anyone could do at home), I do wish the warranty period (1 year parts/labor) was longer. No one used to an SSD is going to be blown away by the speed of a mechanical hard drive over a USB 3.0 connection, but performance does still matter. I was relatively pleased with it when copying mixed media folders (I backed up yet another cache of all of my kids’ baby pictures and videos). Using benchmarking software, I got a maximum read of 257MB/s read and 252MB/s write.Random reads/writes were considerably lower, however, which is to be suspected. The sustained write when transferring that folder of videos and pictures was sustained at about 120MB/s, but it was coming from a drive that wasn’t particularly fast as a source, either. But for a giant storage drive, I’m happy enough with the performance. Overall, it’s a *lot* of storage–it almost makes me queasy to think of that much data on one drive. But I’m using this in conjunction with my other backup drives, and this has so much capacity it’s going to end up backing up several other multi-terabyte storage drives. It’s certainly worth considering if you’re looking for a massive amount of data storage and don’t want to deal with an internal drive (or if you don’t have a spare drive bay).

The Seagate Expansion 20TB is a device that just quietly does its job without asking for attention. It’s straightforward, reliable, and really just about as plug-and-play as storage gets. Getting it running took only a couple of minutes. Out of the box, you pick the right plug adapter for your region (Seagate includes seven different ones, which is pretty generous), snap it onto the power brick, and connect the drive with the included USB micro-B to USB-A cable. The drive comes pre-formatted in exFAT, so both Windows and macOS recognize it immediately. I tested it on a Windows 11 PC and a MacBook and had zero issues. Physically, it’s what you’d expect: a black box that doesn’t scream for attention but feels sturdy enough to just sit on a desk or shelf and do its thing. There’s no bloatware, no setup hoops, and Seagate’s quick-start guide is almost unnecessary because of how simple the process is. On paper, it’s a 20TB drive, but in practice you’ll see closer to 18.2TB of usable space. This is normal, as it’s just the way manufacturers and computers measure storage differently. In my testing with a USB 3.0 port, I saw read/write speeds in the 220–230 MB/s range, which is solid for a high-capacity spinning drive. It’s not SSD-fast, but more than capable for backups, large media libraries, or general bulk storage. Noise and heat are both surprisingly low for something this size. You’ll hear a faint hum when it first spins up, but once it’s running, it’s quiet enough to forget about even when moving large files. The Seagate Expansion 20TB is about as no-nonsense as external storage gets. Huge capacity, easy setup, quiet operation, and broad compatibility. If you need a massive pool of storage without any extra fuss, it delivers exactly that.

Its huge capacity, manageable size and sleek-yet-simple enclosure makes for a nice package, but not without drawbacks. The primary issue in my experience on Mac is an occasional, considerable hit to performance when the drive is starting up. This startup can be slow, sometimes hanging my fairly new Mac mini for up to around 10 seconds. Usually it only prevents accessing the files for this time, but it’s a drag if it happens. On one hand, I understand it. You’re likely getting this platter drive for backup purposes, it’s dense with storage and logically takes a bit longer to access all of it. On the other hand, some might just see such a good price per TB and wish to use it as a general storage expansion. To those people I’d recommend looking at a faster drive, one that can more adequately load and run programs quickly. Even better would be to explore an SSD for speed if that’s your goal. But for those looking for a local backup at an affordable price, these compact mega drives are nice. At 20 TB, I have more storage than I need. I won’t rely on this alone for backup, but it’s nice to have local storage in addition to my (seemingly) safer online storage setup. Due to the above annoyances, I find myself ejecting this drive when not actively backing up. I’m not sure it would be my choice if running an auto-backup program, simply due the load times on Mac and potential for interruptions. I’m not using this with a PC, so it’s worth noting that this drive may actually perform better in that world, so keep that in mind. Using Time Machine on Mac may also work fine if configuring it to backup only after working for the day. Regardless, I find my drive to be fairly quiet while in use. Only a few typical drive noises occur from time to time. These mild sounds would like be more constant when accessing data from it more readily. I appreciate its relatively small form factor though. Its black plastic enclosure is simple but professional looking, blending into my desk environment. Only two cables at the rear, one of which is an uncommon USB interface, making it effectively proprietary. The other is basic power cable and brick that comes with a whole slew of international plug adapters. This seems a bit wasteful as I’ll never need these and collectively they weigh about a pound. Rubber feet are only provided on the narrow side, but I usually lay it flat for better assurance against tipping it over, which could potentially damage the drive should that happen. Overall, I’m happy with this as a purely manual backup drive. It has an incredible price for the massive storage it provides and meets my backup goals. I’d personally choose a faster drive if using an auto-backup feature/software. It’s tendency to take upwards of 10 seconds on Mac to access it’s files makes it too cumbersome to treat as general extended storage.

In 2025, this isn't a daily driver kind of device. NVMEs are cheap enough that you're running your day to day tasks on that. But for bulky files that don't need to be accessed at lightning fast speeds, that's where a drive like this is going to shine. Setup is as easy as most any external hard drive. Plug it in (including the external power supply which contains what I have to assume is every adapter used in every country) and it's ready to go. It's already formatted in exFat so no matter what kind of system you're using, you can probably access this thing. You could always reformat it in any type of filesystem you'd prefer. Usage is pretty good for an external drive like this. When it goes to sleep, there may be a handful of seconds that it hangs your system while it boots up again. Not ideal but I've seen it in most of these externally powered hard drives. Speeds are perfectly fine for a 7200RPM platter drive. You're not (hopefully) editing videos on this thing but if you're running backups overnight or accessing media files, you really don't need anything more. I also expected more noise but it's really not that bad. The build quality is really nice for me. I like more minimalist designs and the enclosure for this is fairly sleek. Just some rounded corners and a slanted line pattern on the top. It's got ventilation on 3 of the 4 sides. I do wish the interface was just USB-C instead of the extended USB micro plug you find on a lot of older hard drives, though. My usage for this is going to be predominantly storing media files on my media server and it can do that just fine. I don't need massive read and write speeds. I just need a lot of space and this ticks that box perfectly. Bottom line, if you're looking for a device that can backup all of your devices overnight or something to just store media on for playback, this is going to be a good fit for you. It's huge capacity is what you're buying here. If you need speed, look at some NVME drives but you'll be sacrificing a lot of storage space. It's a tradeoff. The best option is combining both and using them for their specific use cases.

I’ve been meaning to pickup an external back-up drive for my girlfriend’s computer as all her stream recordings have filled up the internal drives. I wanted one that was simply Plug-&-Play with a high capacity, ideally more than 18TB so we don’t have to get another drive anytime soon. I saw one of my tried and tested brands, Seagate, so I decided to go with one of their Expansion 20TB External Drives. Pros: - Simple Plug-&-Play. - 20TB Capacity. - Multiple power plug adapters. Cons: - Only 1 year warranty. - Toolkit doesn’t support backup for Expansion Drives. Setup: Seagate makes it very simple to use the External Drive. Just unbox, pick the right power plug for the adapter, slide it on, then plug into the power and USB-A to a PC. Done! The drive is already formatted and ready to use, windows 11 detected the drive without any hassle. You could use an adapter to connect via USB-C if needed, but I find the USB-A port to be more compatible than USB-C with PC’s. Seagate includes some getting started guides with the drive, but I’m mainly going to use the Drag and Drop method first to ensure we can clean up the drives. After that, I’ll try using a backup software to automate the backup, I wanted to use the Seagate Toolkit but this drive isn’t currently supported for Backup features I want to use. Power Adapters: As mentioned, Seagate includes 7 different adapter plugs for the power adapter of the Expansion Drive. This allows you to use the external drive in almost any location globally, though I don’t plan to travel anytime soon, this is a convenient feature for an external drive. Drive Capacity & Speed: The drive is labeled as 20TB, though this comes out to 18.2TB of actual useable space in an OS because manufactures measure drive size by 1000 bytes Vs. Software measuring by 1024 bytes. This is standard practice for the industry, don’t waste time complaining about 2.3% of the drive storage. Internally, this is a Seagate BarraCuda ST20000DM001, which has a maximum interface data transfer rate of 600MB/s and a Max Sustained Data Rate of 190MB/s with a Cache of 512MB. In my testing, which was using CrystalDiskMark on the 1GB test, I received speeds of 257MB/s Read and 256MB/s write. Which makes sense. As I was only writing 1GB the first 512MB would have transferred near the 600MB/S (really ~560MB/s) limit then slowed down to the 190MB/s limit. Which means for writes near 512MB you will receive faster write speeds, once you start moving files over 512MB you will start to see speeds around 190MB/s for write. Either way, for a backup drive, this is perfectly fine. Sound: For such a high-capacity drive, the Seagate Expansion Drive is quiet while running. I can tell it is on by the low hum, but I only notice it when powering the drive on. Once running, it is relatively quiet even when in use. Warranty: The biggest downside to this Expansion Drive is that it comes with only a 1-year warranty, whereas most of the base drives come with 5 years warranty. This might be a good trade off if you need the portability or external package all together. But it could be just about the same cost to pickup the bare drive and an external enclosure. Conclusion: If you need a high-capacity external drive that is simple to use and just works, Seagate Expansion Drives are the way to go. Everything is included in the box to get going in minutes with no extra software needed. If you want something with a bit more automation or software, you might want to go another route or find a third-party software that supports the features you want. Overall, I’ll continue go to Seagate for my PC Storage needs as I get exactly what I’m expecting.

PROS Massive 18.1TB usable storage No additional drivers needed for Windows Includes Data Recovery Services with Purchase CONS Rotating HDD will never match speeds of SSD Antiquated USB 3.0 interface Needs an external power source Data Recovery Services require drive to be sent to Seagate USE There isn’t a whole lot to write about the Seagate Expansion hard drive. It is a massive 20TB 3.5” spinning drive housed in a small enclosure. That 20TB equates to 18.1TB of usable storage once formatted. Using my latest Asus V500 desktop, enabling Windows Write Caching in the Policy Settings, and a 5Gb USB 3.0 port, I achieved the following file transfer times: 1GB – 27.35 seconds 3.42GB - 12.14 seconds 16.1GB - 1min, 5.14seconds Yes, the 1GB file took nearly twice as long as the 3GB file. I find that Windows accesses the drive on a regular basis to index files. If you happen to try a read / write command to the drive during this time, transfers are slow and take a bit. If you request a read / write command when the drive isn’t being accessed, speeds are very good. Much better than many other drives on the market. Just over 1 minute to transfer 16GB to a spinning hard drive is quite good. CONS Windows Indexing Services (enabled by default on all Windows PC’s) can affect overall transfer speeds. The Data Recovery Services offered by Seagate with purchase of the drive are not included in a separate partition on the drive. Should the drive fail, you must send the drive to Seagate for extraction and recovery. Seagate will then send you back an encrypted thumb drive with any data they are able to recover. I understand why Seagate chose to do this, but I don’t necessarily agree with it. I don’t like storing sensitive data on an external drive and if it fails, needs sent to a 3rd party that, in turn, would have access to that information. FINAL THOUGHTS The Seagate Expansion hard drive offers a TON of storage at a reasonable price. 20TB will hold a bunch of data and while nVME’s and SSD’s are all the rage, they can’t compete with a good, old-fashioned spinning drive for storage and price. I’ve used Seagate Iron Wolf drives for years and have had excellent reliability with them. I’m hoping the Expansion drive continues my success. If you need a massive amount of storage with speedy transfer times, the Seagate Expansion external HDD deserves a look. RECOMMENDED

This is a good basic backup/storage solution in a relatively compact enclosure. Connected to the USB 3.0 port on my router, I’m able to use this as a network storage device and backup whatever files I need to on it. The package includes the hard drive, power adapter, and a USB cable. The connection on the enclosure is a USB micro-B, which feels like an odd choice, but seems to be pretty common for these large external HDD’s. The required power adapter uses a standard DC barrel connection and is rated for 18W. The enclosure is made of plastic and is around 25% larger overall than the HDD itself. The drive is made to be positioned vertically on its rubber feet, but I had no problems laying it down horizontally and it does not block any ports or ventilation. The drive is ventilated on 3 sides. The hard drive within is a SeaGate BarraCuda 20TB 3.5” 7200RPM drive with 512MB of cache. The actual storage capacity reported by Windows is 18.1TB. I recorded read/write speeds between 250-260 MB/s, which is good for a mechanical hard drive. This was over USB 3.0 connected directly to my PC. I did notice that the drive runs warm, but it was nothing that caused me any concern. There is a 1-year includes warranty and Seagate also includes a data recovery service. You can check the validity of the data recovery service plan on Seagate’s website, though it’s not clear to me how long this service is valid for and what you get with it. From what I could find, it seems the plan is valid for a singular data recovery attempt within the warranty period of the drive, which only being 1-year likely means you won’t be able to make use of it as the drive is unlikely to fail within this period of time unless it’s defective. Overall, I’m happy with the external drive as a basic storage solution for my media and files. It has a simple job and it does it well.

Right out of the box the external hard drive worked just as it needed to. It’s capable of storing just under 20TB of my videos, photos and documents easily. Data transfer speeds are pretty good. It comes with multiple international plug options which I have never seen before with my older Seagate expansion external hard drives. Form factor is not much different than any other hard drive and operation is the same. Plug it in, start to download and transfer data. What more can I say about it other than seagate has been my trusted go to external hard drive provider for as long as I could remember. In the years in which I’ve used seagate products their customer support has always been easily accessible, available and ready to assist if needed. I’m hoping that still rings true. The quality of their drives has always been top notch. Now the only negative I can speak on is that I wish that it was usb-c. It does state that usb-c ports require a micro-b to usb-c cable but it’s not included. That should’ve been included especially if they provided many international plug options that would most likely never see the light of day. Anyways, just like any other external hard drive that isn’t exclusively for Mac, you will have to reformat the drive, especially when using it with Time Machine.

At the time I bought this device, it offered the best consumer price per TB in a large storage device. It presented no challenges in initial setup (worked right out of the box), or subsequent performance. Note, it is a mechanical HDD, not an SSD, so expect the performance (and noise) of one. It's good as auxiliary/mobile storage, but not recommended as the main (OS) storage of a modern computer, both due to its parameters driven by being a mechanical hard disk drive, and connectivity via a 5Gbps USB, not the fastest nowadays. And back the pros - consider your use case and the price. If what you need is large volume auxiliary storage, and extreme performance is not at the top of your priorities - this is a great choice.

At first I was confused as to why a 20 TB drive only showed as a little over 18 TB available. I had not encountered that situation before. “Missing” two TB seemed like a big deal. Curious, I did some research and learned that Windows reports storage capacity using the binary numbering system where 1 TB is equal to 1,099,511,627,776 bytes. So 20,000,041,598,976 bytes would be reported as 18.1 TB. I did run Window’s built in disk checking program which confirmed there were no errors or bad sectors. So there is no missing storage capacity at all. On a smaller drive I never noticed the difference but on such a large drive it was noticeable. Learn something new everyday! I then opened a command terminal and ran the Windows System Assessment Tool to view the read and write speed of the drive. I made sure I was plugged into a SuperSpeed 10 port, probably overkill but I wanted to be sure I was getting the best possible performance. Windows reported a sequential 64.0 read speeds of 189.66 MB/s and a sequential 64.0 write speed of 246.01 MB/s. I did try the test again but with it plugged into a standard usb port and it reported read/write speeds of 38.8/32.8 MB/s so do be sure to use the fastest port available on your computer, a 3.0 at a minimum. The case of the device measures 7x5x1.75 inches and is well ventilated. I appreciate that it comes with an 18” long usb 3.0 cable since my usb port is near the top of my pc case and the longer cable gives me some slack so I had options on where to place the drive. It comes with a power supply with no less than seven different plug adapters if you travel internationally with it. The drive included Seagate’s Rescue Data Recovery Service which is a mail in data recovery service where data recovery experts will attempt to either repair a hardware failure or repair logical damage to the filing system in order to recover your data. I am using this drive for two purposes. Since it’s portable, I’m attaching it to each of my laptops and PCs to perform a back up using the Windows Back Up app. I have to attach it to each computer because I have Windows 11 Home version which apparently does not support accessing an external drive across a network like the Business or Enterprise versions do. I thought I could attach the drive directly to my router’s usb port and access it that way but my router does not support that. So I will just move it from computer to computer. Not as convenient as an automatic back up but certainly better than nothing! I’m also using it attached to my main PC to store photos, movies, and video clips sent from my surveillance camera’s NVR. With the large capacity of this drive I expect it will take a long time to fill.

There is not a lot to say about a hard drive like this external 20TB (18TB usable) Seagate Expansion drive aside from noise, speed and does it work. Over a week of use and having loaded it up to about 14TB. Speeds are typical for HDD over USB, rather slow unless the files are small. Typically about 50mb/s, sometimes double that, sometimes half that when moving 2gb+ files. So far, it works and no odd noises. PC "see's" the drive each time I boot up and has yet to drop connection whether writing or reading. Wake and sleep times are acceptable. It is possibly quieter than my slightly older 12TB external I got from another brand and that one is only audible when I get up next to it. I keep the drive out in the open on a shelf of my living room near a laptop I use regularly for media. Hard drives may click from time to time and will never be dead silent like an SSD, but SSD's are nowhere near affordable for 20TB yet either. Other than wishing these would switch to USB-C and be powered and transfer on that single cable. These external drives are the best way to keep me grounded to my media and files and avoid the cloud and all the fees associated with a random company holding MY personal stuff. Ultimately, these external drives are the way to go for storing excess files, archived collections or just as a backup to smaller free cloud storage that hold some of your stuff. They are easy to power and access even if power goes out (UPS) and you lose access to the internet for whatever reason. Granted, it is debatable how long drives last, but I found every 5 to 7 years the size increases so wildly that I tend to recopy all my files to the new drive in that time that its not a problem. But, I am an old guy and I have lived long enough to remember storage used to be MB not even close to GB and now with TB, I wonder if I will live to buy PB storage devices. Everyone should have at least a small backup drive if the Expansion Drive is more space or expense for you at the moment. This Seagate says 3 year warranty on the box. And that's a decent amount of time to have assurance that a device will do its job.

Unpacking drive was simple as it is already formatted using exFAT. Comes in a nice black lightweight well-ventilated plastic enclosure. Comes with 48-inch USB-C micro to USB 3.0 connection cable and 70-inch power cord with slide in power plugs which should allow for use anywhere in the world. Unfortunately, the downside is power cord has a large power block that pretty much blocks at least 2 plugs in a power strip. Overall, this 20TB external hard drive checks a lot of performance boxes. According to CrystalDiskInfo the drive is a 3.5-inch SATA III Seagate model ST0000DM001-3Y3103 with 7200rpm and 512MB cache. It also indicated a temp of 122F – a tad concerning as drive was inactive. In CrystalDiskMark 8.5 speed tests it compared very favorably in read speeds to my WD 10TB Blask “gaming” 3.5-inch internal drive. It did fall a tad short in write speeds though. Also drive “clicks” – usually when booting the system or when waking from sleep mode. It was quiet as I tested copying files to/from it. But it was distracting enough that I moved it from my large metal desk to an adjacent wooden shelf. 1 year warranty – which is a tad disappointing. No on/off switch but it does have a small light signifying it is on. Stated 20TB but only 18TB is usable. No USB-C micro to USB-C cable supplied but can easily be purchased. Overall, a decent drive at a nice price point. I do recommend it if you need a large portable external drive. But if you have a desktop, I would go with the internal version.

20TB is probably more than I need, but the dollar per a TB makes this a pretty good bargain. This is still a mechanical hard drive so don't expect it to be too quiet. This is fairly compact for 20TB's as well.

Great addition to my set up. Provides about 18TB after everything is said and done. More than enough space for any video editing and gaming I plan to do.