Shark Clean & Empty Cordless Stick Vacuum & Auto-Empty System BU3521 10" Cleaning Path White: Bagless, 40 Min Run Time
$249.99 reg $399.99
Sale save $150.00 (38% off)
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The Shark cordless vacuum offers a powerful and convenient cleaning experience with its auto-empty feature, making it ideal for quick cleanups. Guests appreciate its lightweight design, maneuverability, and ability to transition between different floor types seamlessly. While some have noted durability concerns and average suction power, many find it effective for daily use, especially in homes with pets. Overall, it stands out for its innovative features and ease of use, making it a worthy investment for any household.
Summary created by AI from text of reviews reflecting recent feedback provided across different star ratings (includes incentivized reviews)
4.0 out of 5 stars with 282 reviews
45% would recommend
35 recommendations
2 out of 5 stars
28 March, 2026
originally posted on sharkninja.com
Sucks not in a good way
This vacuum is horrible. It clogs, it just moves hair around. I change filters and empty but it doesn’t work well at all. I have hard floors, no carpet. I have to sweep with a broom first into piles so it will pick up dirt and pet hair. I have a lab and a cat. I have a rug at my front door, and it basically has to be picked up and shaken outside. Pet hair just gets pushed around not picked up. It clogs at the bend where the brush head goes into vacuum. I had to buy a brush to clean it. Now it won’t self empty! I dumped it and changed filters now it won’t work Had it for about a year and a half and it never worked. Piece of junk!
1 reply from Sharkninja team - 4 days ago
Hi there, Thank you for taking the time to share your feedback. We're truly sorry to hear of your experience with this and we understand how incredibly frustrating it is to deal with repeated clogs, poor pickup on hard floors, pet hair pushing instead of lifting, and now issues with the self‑emptying feature, especially after trying fresh filters, emptying the bin, and manually cleaning the brush head. We truly appreciate you outlining everything you’ve been through, and your feedback is valuable to us as we continue improving our products and support. To help troubleshoot what’s happening with your vacuum, we recommend referring to our self‑help guide here: https://support.sharkninja.com/en-CA/article/BU3000-BU3500-Series-Shark-Clean-Empty-Cordless-Stick-Vacuum-Auto-Empty-System-Troubleshooting-Guide-ca If the steps do not resolve the issue, please follow the directions provided at the end of the guide so our team can assist you further. Kind Regards, Shark Home.
5 out of 5 stars
Thumbs up graphic, would recommend
22 March, 2026
Delightful!
At the risk of sounding totally unhinged, this vacuum has made cleaning up after my dog and kids an absolute delight. I don’t mind vacuuming but my old corded Shark stuck vac was a pain to get out, assemble, wrap the cord, dump the canister, and disassemble for storage (4x a day). So it basically lived in the middle of the kitchen, plugged in, waiting for the next mess, tripping the unsuspecting passerby and annoying my husband to no end. I got 10+ years out of the last one so I didn’t feel too terrible about splurging on this new model when ours finally bit the dust. I’ve had this for less than 24 hours so I can’t speak to its longevity but I’ve tested it on every surface in our home and it does amazingly well on tile/hardwoods/low carpet and I love how it auto adjusts to each surface. The speed with which I can bring it out and put it away is a huge relief and makes me wish I’d bought this much sooner. Hoping it stands the test of time as well as our previous Shark.
1 out of 5 stars
19 March, 2026
originally posted on sharkninja.com
Horrible Product
This vacuum is a complete disappointment. It won’t close properly after emptying because small pieces of metal get stuck in the magnetic flap. There’s also a weird internal compartment that fills with dirt but can’t be cleaned—completely useless design. To make matters worse, it randomly shuts off while vacuuming. Extremely frustrating and unreliable. Worst vacuum I’ve ever owned.
1 reply from SharkNinja team - 12 days ago
Hi there, Thank you for taking the time to share your experience with the Clean & Empty Cordless Stick Vacuum & Auto-Empty System. We are very sorry to hear about the difficulties you have been facing. It should never be a struggle to close the bin after emptying, and debris getting caught in the magnetic flap can certainly make the process frustrating. The unit shutting off in the middle of use is another issue we do not want you to experience. Sudden power loss can sometimes be related to airflow, connection points, or internal components, and our team would like to take a closer look so we can help determine what is going on. When you have a moment, please reach out to us through the link below so we can assist you directly: https://support.sharkninja.com/contact-us Sincerely, Shark Home
2 out of 5 stars
Thumbs down graphic, would not recommend
18 March, 2026Verified purchase
Not self-lpropelled
Not self propelled at all and difficult to move on carpet. Feels cheap. Not as great as their other products.
1 reply from SharkNinja Product Expert team - 12 days ago
Hi Lindsey, Thank you for sharing your feedback with us. We’re really sorry to hear that your vacuum feels difficult to move on carpet, isn’t providing the self‑propelled feel you expected, and comes across as cheaper than your previous Shark products. We understand how disappointing that is, especially when you’ve had better experiences with our products in the past. If you’d like us to take a closer look or go over any options that may help, please give our support team a call at 1‑855‑427‑5127, Monday–Friday 9 a.m.–9 p.m. ET | Saturday 9 a.m.–6 p.m. ET. Kind regards, Shark Home
1 out of 5 stars
Thumbs down graphic, would not recommend
11 March, 2026Verified purchase
Not for pet hair, clogs easily, poor suction
Poor suction, clogs very easily. If you have pets, don’t waste your time with this vacuum. It was decent at first but the entire tube from the brush to the dirt cup clogs up after each use. It will barely pick up fur and dirt and just drags it around under the brush. I wanted to love this vacuum since I am very happy with my corded Shark rocket and my shark robot but I was disappointed. If it was half the price, I would still have returned it.
1 reply from SharkNinja Product Expert team - 19 days ago
Hello Beth, Thank you so much for sharing your feedback. We’re truly disappointed to hear that the Shark Stick Vacuum didn’t meet your expectations. We understand how frustrating it can be when the suction doesn’t perform well for pet hair, the brush roll and canister clog after each use, and the roller pushes debris around instead of picking it up. This isn’t the experience you deserve, and we appreciate you bringing it to our attention. We do encourage you to give us a call at 1-855-427-5127. We're available Monday through Friday from 9:00 a.m. to 9:00 p.m. ET, and Saturday from 9:00 a.m. to 6:00 p.m. ET. Kind regards, Shark Home
5 out of 5 stars
9 March, 2026
originally posted on sharkninja.com
Sleek Vac
I have had this for 3 weeks and I am very pleased with its performance. I have a husky and an infant so there’s chaos in my house and this vac has the suction we need to keep our spaces clean for our little bub. I love that it’s easy to use, has its own empty bin and it charges itself without me remembering to press a button.
4 out of 5 stars
4 March, 2026
originally posted on sharkninja.com
Lightweight
I’ve had this for about 10 months, does the job. Very light weight and I love it has the automatic change from flooring to carpet. I do wish it had some sort of rubber on the battery part for when you stand against a wall it won’t slip.
1 out of 5 stars
2 March, 2026
originally posted on sharkninja.com
Unsatisfied
I’ve had this product for about 1 to 1/ 2 years. It is a great concept the self emptying canister however I have had lots of trouble with it closing properly after the emptying. If the tinesr but of metal gets stuck in the magnetic canister closure it doesn’t fully close and thus doesn’t vacuum effectively. I have to find supplies to fully clean the magnetic section to allow for proper closure. From the tiniest metal shavings to staples get stuck in here. There was an also a small compartment inside the canister that immediately filled with dirt that has no way to be removed. I’m not even sure of the purpose of this compartment. Very short battery life on max suction setting. Should have stuck with my Dyson
1 reply from SharkNinja team - 27 days ago
Hi Mcgoffinm, Thank you so much for taking the time to share your feedback with us. We are very sorry to hear about the trouble you have been experiencing with the self‑emptying canister, as we understand how frustrating that can be. We will pass your comments along to the relevant team. In the meantime, you can try the troubleshooting steps in the link below. If the issue is not resolved, the page will direct you to our Customer Service team for further support: https://support.sharkninja.com/en-CA/article/BU3000-BU3500-Series-Shark-Clean-Empty-Cordless-Stick-Vacuum-Auto-Empty-System-Troubleshooting-Guide-ca Kind regards, Shark Home
1 out of 5 stars
28 February, 2026
originally posted on sharkninja.com
Not happy
Had this vacuum a year now doing mostly hardwood and tile floors and the pistol grip handle the battery mounts broke off the housing rendering it useless
1 reply from SharkNinja team - 30 days ago
Hello there, Thanks for leaving an honest review. It disheartens us to learn that the grip handle the battery mounts to broke off the housing, and you're unable to use your vacuum. This is not the experience we want for our customers. We do see that you contacted our team recently, and we followed up with an email. Kindly respond to the email sent so we can resolve this for you. If there’s anything more we can do to help, or if you’d like to share additional details, we’d love to hear from you. Please feel free to reach out to our Customer Care team at: https://support.sharkninja.com/contact-us Kind regards, Shark Clean
5 out of 5 stars
Thumbs up graphic, would recommend
23 February, 2026Verified purchase
Better than the Dyson
I returned a Dyson in exchange for this one. Right out of the box the Dyson wasn’t picking everything up. Looked up some reviews, which lead me to this Shark vacuum and it is much better! Powerful suction. Picks up hair and dander no problem in one pass. Plus I love the automatic empty feature. My only note is that the floor roller gets stuck upright vs the angle for cleaning but you can push it back into place in a second.
4 out of 5 stars
22 February, 2026
originally posted on Shark Ninja ANZ
Good … but
Thank you Mrs Stoddy you have confirmed my initial investigation. I tried to remove and clean the small element in the unit dust container without causing damage: seems like it’s not meant to be removed or cleaned!
1 out of 5 stars
19 February, 2026
originally posted on Shark Ninja ANZ
Disappointed
Will be returning with the warranty as it does not perform as it should due to multiple design flaws Causing blockages, In adequate emptying, Power in suction decreases after the first few minutes of use. However I love Shark products but this hasn’t been a disappointment.
1 out of 5 stars
11 February, 2026
(no review title)
Horrible - dies every 5-10 minutes. Get a vacuum with a cord.
1 reply from SharkNinja Product Expert team - 2 months ago
Hello Alexis, thank you for sharing your feedback. We’re truly sorry to hear about your experience. You mentioned that your unit dies every 5–10 minutes, which is incredibly frustrating, especially when you're simply expecting a reliable clean. This is definitely not the experience we want our customers to have, and we completely understand why you’d feel disappointed. We’d really like the opportunity to look into this further and help get things back on track for you. Please don’t hesitate to reach out to our customer support team at 1‑855‑427‑5127, available Monday to Friday from 9 a.m. to 9 p.m. ET and Saturday from 9 a.m. to 6 p.m. ET. Your concerns have been noted, and we’ll take the appropriate steps to get this resolved. Kind regards, Shark Clean
5 out of 5 stars
30 January, 2026
originally posted on Shark Ninja
Better than my Dyson
I purchased this 8 months ago and it still works great. It was so easy to use straight out of the box. I really love the auto empty system. It saves time and mess. I think it cleans better that my old Dyson. I bought it when my Dyson broke and a new Shark was just cheaper. I am not disappointed.
1 out of 5 stars
Thumbs down graphic, would not recommend
24 January, 2026Verified purchase
Save your money do not buy this vacuum
This vacuum is not worth the money. It often gets stuck in carpet mode even when used on hardwood floors, and instead of picking up dirt, it just pushes dust and small debris around. Overall, it’s completely ineffective.
1 reply from SharkNinja Product Expert team - 2 months ago
Hi there, thank you for sharing your feedback. We’re truly sorry to hear about your experience, especially concerning the vacuum's performance. It’s disappointing to learn that it gets stuck in carpet mode even when used on hardwood floors, and that it seems to push dust and small debris around instead of effectively picking them up. We understand how frustrating this can be, and it's certainly not the experience we want our customers to have. To assist you in resolving these performance issues, we encourage you to reach out to our customer service team. They are available at 1-855-427-5127, Monday to Friday from 9 a.m. to 9 p.m. ET, and Saturday from 9 a.m. to 6 p.m. ET. Your concerns are important to us, and we are committed to taking the appropriate steps to improve your experience. Kind regards, Shark Clean
1 out of 5 stars
22 January, 2026
originally posted on sharkninja.com
SHARk clean and empty cordless vacuum &auto empty
I’m so disappointed with this product. My daughter and son-in-law gave this vacuum as a Christmas gift. I have had this les than a month and it stop working. My daughter came over and took a good look at it to see if she could fix it it. We cleaned it, check the hoses etc nothing. It just stopped working.
1 reply from SharkNinja team - 2 months ago
Hi Carolyn, Thank you so much for taking the time to share your review. We’re truly devastated to hear that your Shark vacuum stopped working so soon after being gifted for Christmas. We completely understand how disappointing and frustrating this experience must have been, and we'd like to help resolve this for you. Please know that your feedback is incredibly valuable, and we’ll be sharing it with the appropriate teams internally to ensure it’s fully reviewed. In the meantime, we recommend referring to our self-help guide link below to troubleshoot the issue you're experiencing: https://support.sharkninja.com/article/BU3000-BU3500-Series-Shark-Clean-Empty-Cordless-Stick-Vacuum-Auto-Empty-System-Troubleshooting-Guide. If the issue continues after trying those suggestions, follow the instructions at the end of the guide to reach our support team for further help. Kind regards, Shark Clean NA.
1 out of 5 stars
Thumbs down graphic, would not recommend
21 January, 2026
(no review title)
Liked this for a year and now the battery goes dead after about 2 minutes
1 reply from SharkNinja Product Expert team - 2 months ago
Hello Morgan, thank you for sharing your feedback. We’re glad to hear you enjoyed your vacuum for the first year, but we’re truly sorry to hear that the battery is now running out after just a couple of minutes. That’s definitely not the performance we want for out customers. We’d really appreciate the opportunity to help diagnose what’s going on. Please reach out to us at 1-855-427-5127 (Monday to Friday: 9 AM to 9 PM ET and Saturday: 9 AM to 6 PM ET), and our team will be happy to review your options and work toward a solution. Kind Regards, Shark Clean
5 out of 5 stars
21 January, 2026
originally posted on Shark Ninja
best product
best product amazing loved it i was looking for good vacuum found one
5 out of 5 stars
19 January, 2026
originally posted on sharkninja.com
Easy to use
Love this vacuum!!! It is light weight, easy to use and empty! Has good suction.
1 out of 5 stars
Thumbs down graphic, would not recommend
17 January, 2026
(no review title)
This is the worst vacuum. Constantly gets clogged by regular dirt. Not picking up anything crazy and it all bundles up and get stuck in the tube. I’ve never had that issue with a vacuum.
1 reply from SharkNinja Product Expert team - 2 months ago
Hello Brittany, Thank you for sharing your experience. We understand how frustrating it must be to have your vacuum constantly clog with regular dirt, especially when you’re not picking up anything out of the ordinary. This isn’t the experience we want for you, and we appreciate you letting us know what’s been happening. We’d love to take a closer look to make sure your unit is operating as intended, so please feel free to give us a call at 1‑855‑427‑5127, as we hope to ensure we remain a trusted brand in your home. We're available Monday–Friday: 9 a.m.–9 p.m. ET and Saturday: 9 a.m.–6 p.m. ET. Kind regards, Shark Clean