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Roomba S9+ Review: Best Robot Vacuum Ever?

Our tests of the newest iRobot vacuum are finally here with the Roomba S9+ review!

Most Advanced Roomba with Self-Emptying Dust Bin

Roomba S9+ robot vaccuum

Roomba S9+

The Roomba S9+ is arguably the most advanced robot vacuum ever built. It performed exceptionally well in our cleaning tests, removing 99% of all debris across 3 different floor types and against 4 different debris types. The new square front is designed to help improve cleaning in corners / edges. Sensors and cameras ensure great navigation. But the best part is it can empty its own dust bin (up to 30 loads before you need to empty bag). Easily one of the best robots on the market (if not the best).Check Price

Pros

  • Square front body style may provide advantages at cleaning edges and corners
  • Automatic emptying dust bin, much like the Roomba i7+ model
  • Smart navigation with zoned cleaning and digital mapping
  • Excellent cleaning performance (scored 99% average on our tests)

Cons

  • Very expensive price point
  • Not immune to getting stuck (though it is better than most)

If you would rather watch than read a review, you can find our complete Roomba S9+ video review below:

Table of Contents

7 Month Usage Test

Roomba S9+ cleaning hardwoods

We’ve been testing the Roomba S9+ in our lab and in-home over the last 7 months. During the last 7 months the S9+ has:

  • Completed 92 cleaning jobs
  • Vacuumed for 78 hours and 38 minutes
  • Emptied its own dust bin 95 times

Within the last 30 days it has vacuumed 19,200 square feet. Over the last month we’ve been letting the S9+ clean several times per week.

Roomba S9+ cleaning history
Roomba S9+ cleaning history
Roomba S9+ cleaning history chart
Cleaning history chart

The home where most of our testing occurred is 2,600 square feet and single story.

What’s To Like

  • Excellent cleaning performance. During our lab tests and extended in-home tests the S9+ was an amazing performer. It has more than enough suction to handle just about any debris and any floor type. Our floors are as clean as they’ve ever been.
  • Smart floor mapping. As the S9+ cleans it learns your home’s floor plan. It takes 2-3 sessions to fully create the map. Once mapped, you can setup room divers, room names, keep out zones, and more. This lets you really take control over how / when / where your home gets vacuumed.
  • Self-emptying dust bin. It’s a feature I knew I would like, but didn’t fully appreciate until I got used to it. It just cannot be overstated how nice it is to only need to empty once every 1-2 months. The self-emptying dust bin really takes over the entire vacuuming chore.

What’s Not So Good

  • Still Can Get Stuck. Even though the S9+ is incredibly smart, it’s not immune to getting stuck on weird obstacles, shag rugs, cords, etc. The biggest issue we noted was that it frequently got stuck in our bathroom mat. We reached a point where I would just pickup the mat beforehand or close the door to avoid the issue.
  • Large and complex floor plans take a long time. With re-charge and resume the S9+ will keep cleaning until its done. That said, if you have a larger or more complex floor plan it can take a long time (several hours) to fully finish. To resolve this, we setup a smart map with a keep out zone, letting the S9+ vacuum one side of our home, while the Roomba i7+ handles the other. Granted, if you aren’t home during the day this really isn’t as big of an issue.

Overall, I’ve been impressed with the S9+. It feels like the next big step for robot vacuums, as the self-emptying dust bin feature is a huge add. Performance, navigation, and usability were all solid across the board.

Continue below for our full Roomba S9+ review.

Cleaning Performance & Tests

Unsurprisingly, cleaning performance on the Roomba S9+ was exceptional. It was effectively perfect across all 3 floor type tests.

It scored 99% on all of our tests. See our complete data and before / after photos below.

Overall

99%

Hardwoods

99%

Low Carpet

99%

High Carpet

99%

Roomba S9+ cleaning vs. hardwood floors
Roomba S9+ cleaning vs. hardwood floors
Roomba S9+ cleaning vs. low pile carpet
Roomba S9+ cleaning vs. low pile carpet
Roomba S9+ cleaning vs. high pile carpet
Roomba S9+ cleaning vs. high pile carpet

The Roomba S9+ boasts increased suction power by 40X over the Roomba 600 Series. For comparison, the Roomba i7+ offers 10X the suction power over the Roomba 600 series, so there’s a big jump there.

The Roomba S9+ did miss a couple pieces of debris on each test. However, the amount left behind wasn’t enough to measure on our digital scale.

The Roomba S9+ is the best robot we have tested to date.

RELATED – Wonder how the S9+ compares to other high-end Roomba? See our S9+ vs. S9 vs. i7+ vs. i7 vs. e5 comparison here.

Roomba S9+ Design

The design of the Roomba S9+ is notably unlike anything we’ve seen from the iRobot showroom. This vacuum takes a direct deviation from the round body style and instead uses a square front body style.

Roomba S9+ plus robot vacuum

RELATED – The Neato Botvac D7 is another robot with a square front body style.

The Controls

The controls are also different on the S9+ than any other model we’ve seen from Roomba.

Most other Roomba models have always had a CLEAN button right in the middle of the vacuum. With the S9+, the central part of the vacuum is reserved for a large matte gold accent disk.

Roomba S9 button

The controls are located to the side closer to the straight edge of the D-style body.

Controls include:

  • CLEAN – to start or pause a cleaning cycle
  • HOME – to send the Roomba back to its charging base
  • SPOT – for spot cleaning specific areas in a cleaning cycle

The Underside

The underside of the Roomba S9+ has many of the same parts as older Roomba models, but the design is completely different.

Under side of the Roomba S9+

The brushroll is located at the front of the vacuum, instead of the middle, like it is on traditional Roomba models. Because of its new location, it also has a wider design, since it’s not sandwiched in between the wheels.

Roomba S9+ brush roll
Roomba S9+ brush roll

This longer brushroll provides a wider cleaning path, which could result in shorter cleaning cycles and less navigating back and forth.

There is still a spinning brush on one side to help capture debris from the edges and corners, but the bristles are much smaller than what you’d find on other Roomba models.

Roomba S9 spinning side brush

The bottom of the vacuum also has a small access port that allows the dust bin to empty directly into the CleanBase unit on the charging station.

Automatic Dust Bin Disposal slot

Build Quality

We’ve always been really impressed with iRobot’s build quality. Their robots are built like tanks. They look and feel incredibly well made.

Under neither the hood on the Roomba S9+
Under the hood

However, the build quality on the S9+ really feels like a step up even from that. The parts have a solid feel to them. The matte black plastic parts mixed with the copper accents are incredibly stylish.

Roomba S9+ Plus Robot vacuum

Every part, from the body to brush rolls to base, to even the power cord that comes with it, feels like it’s build to last.

Automatic Dustbin Emptying

Like the Roomba i7+, the Roomba S9+ comes with an automatic dustbin emptying technology designed into the charging base. This system is called CleanBase and is an enlarged charging base system that has a disposable dust bag, which the S9+ can deposit debris directly into.

Roomba S9+ smart cleaning base

If you think you’ve seen this before, it was likely on the Roomba i7+, where the CleanBase was first introduced. The dust bag on the charging base can hold up to 30 loads of debris from the on-board dust bin.

Size & dimensions of the Roomba i7+ Clean Base
Roomba i7+ clean base for comparison

NOTE: Although iRobot advertises the dust bag on the CleanBase as “disposable”, I found that it was possible to simply empty the contents and reinstall the bag. Unless you have serve allergies and don’t want any debris to become airborne, it is certainly possible to empty and reuse this bag.

Edge Cleaning

The Roomba S9+ is the first robot vacuum from the Roomba lineup that has a square front body style. This makes it easier to access corners and along straight edges.

Roomba S9 cleaning low carpets

Wifi-Connectivity

When paired to a wifi network, you can control the Roomba S9+ directly from your phone or via voice control, when paired with technology like Amazon Alexa.

iRobot Roomba smartphone app
iRobot Roomba smartphone app

Imprint Smart Mapping

Imprint smart mapping (ISM) combines a number of smart navigation features into one technology. ISM includes zoned cleaning, navigation in straighter liner, and the creation of digital maps which are accessible directly from your smartphone using the iRobot app.

iRobot Roomba app smart mapping
Smart mapping feature on the iRobot app

Smart sensors designed into this robot digitally scan the space up to 25 times per second, resulting in less bumping into obstacles.

Imprint Link

Imprint Link is a paring technology that works with the Roomba S9+ and the new Braava m6 mopping robot. When used in tandem, this linking technology allows for the S9+ to vacuum for your carpets and then communicate to the m6 that it’s time for mopping.

iRobot Roomba Braava Imprint Link
Using the Imprint Link feature within the iRobot app

The one disadvantage here is that in order to utilize this technology, you’ll need to purchase the robot vac and mop, which would be quite an investment.

Recharge & Resume

As opposed to just making batteries bigger and bigger, iRobot seems to be moving more in the direction of recharge and resume.

This feature allows the Roomba to return to its base and recharge any time it runs out of battery. Then it simply returns to where it left to continue cleaning until the job is done.

Size & Dimensions

Visually, the Roomba S9+ looks to be a similar size compared to other square front robots.

How big is the vacuum?

The Roomba S9+ is:

  • 12.25″ diameter
  • 3.5″ tall
  • 8.15 pounds
iRobot Roomba S9 size

How big is the charging base?

The charging base of the Roomba S9+ is comparable in size to the CleanBase charger on the Roomba i7+.

The dimensions are roughly:

  • 19″ tall
  • 15″ deep
  • 12″ wide
Roomba S9+ clean base size

On the Roomba i7+, you have the option of downgrading to the vacuum without the larger, self-emptying charging base. They package this deal as the Roomba i7.

RELATED See our Roomba i7+ review here.

The Roomba S9 has a a similar package, being available as the Roomba S9+ (with the CleanBase charging station) or the Roomba S9 only (standard charging station).

Depending on your needs, it may make sense downgrade to the less advanced charging station and save some cash if automatic dustbin emptying isn’t an important feature to you.

Accessories & Parts

The Roomba S9+ includes the following accessories:

  • Clean base (both charges and allows S9+ to self-empty dust bin)
  • 2 Disposal bags
  • 1 HEPA filter
  • 2 Spinning brushes (1 extra)
Roomba S9+ accessories

Charging base

The charging base is larger than a traditional Roomba charging base since it has the self-emptying technology and large dust bag designed into the actual unit.

Disposable bags

The S9+ comes with two disposable bags that install directly into the charging base. As I mentioned above, Roomba calls these bags “disposable”, but if you’ve concerned with maintenance costs, you can certainly empty and reuse these bags. On average, they can hold about 30 loads of debris from the on-board dust bin.

Roomba S9 Plus dust bag

HEPA filter

The HEPA filter on Roomba S9+ is the same filters as what you’ll see on the Roomba i7+, i7 and e5. It’s about the size of a cassette tape and a part of the AeroForce system. Roombas with the older AeroForce or the AeroVac system will use a larger, slightly bulkier style filter.

Roomba S9 HEPA filter

While the filters are the same as what you’ll see on other high-end Roomba, it’s able to remove more particulates due to the completely sealed system. Dust is transferred from rollers through the filter, to the bin, and then finally to the dust bag on the base.

Spinning brush

The spinning brush is another accessory that has changed slightly on the Roomba S9+. With the adaptation into the D-style body, the spinning brush on this model is smaller than it is on other round-body robot vacuums.

Roomba S9 spinning brush

Setup & Usability

Setup on the S9+ is similar to setting up any other robot. Unbox it, plug it in, charge it, then turn it on.

That’s about it.

Setting up the Vacuum

All Roombas come pre-assembled. The spinning side brush and brush roll was already installed.

While most Roombas arrive with an almost-full battery it’s still a good idea to charge it up before starting a cleaning cycle of any new space.

One dust bag is already installed in the base
One dust bag is already installed in the base

After a quick charge, you can simply press “CLEAN” and let it get to work, or you can choose to pair it with the app.

Pairing with the app helps to enable advanced features and control, as well as improve overall usability.

Setting up the App

Installing the app takes just a few minutes.

  1. Install the iHome app on your device.
  2. Follow the prompts to pair with the S9+.
  3. Start a cleaning cycle, set schedules, view cleaning performance, or check out recommended maintenance tasks.
iRobot Roomba scheduling
iRobot Roomba scheduling

When connected to a wifi network, you can also control the S9+ with simple voice commands. This does require you to have a voice-activation device like Amazon Alexa or Google Assistant.

Smart Navigation

The advanced navigation and Imprint technology (both for mapping and linking) provide some real advantages in terms of usability.

Smart sensors on the Roomba S9+ scan any space up to 25 times every second resulting in better navigation and less bumping into obstacles.

Sensor bar on the front of the Roomba S9+
Sensor bar on the front of the Roomba S9+

Does the Roomba S9+ have zoned cleaning?

Absolutely. As part of the Imprint smart mapping technology, the S9+ creates digital maps of your home, which you can later assign names to those spaces for specific zoned cleaning.

Roomba S9+ zone cleaning & keep out zones
Roomba S9+ zone cleaning & keep out zones

In addition, you can create Keep Out Zones, which tell Roomba to stay out of those areas.

When paired with Amazon Alexa or Google Assistant you can even access zoned cleaning through voice command.

Simply speak short commands like, “Roomba, clean the living room” and the S9+ will get to work.

Is the Roomba S9+ a good value?

Ok so bottom line… is the Roomba S9+ a good value? Really it depends on what you’re looking for.

The Roomba S9+ is bleeding cutting edge, no doubt about that. If you want the absolute “best of the best”, the Roomba S9+ is the robot vacuum for you.

Roomba S9+ cleaning on hardwood floors

It has all of the most advanced technology and 40X the suction over the Roomba 600 Series. In addition, it’s the only robot we’ve seen to date that has linking technology to pair it with a mopping robot (the braava m6).

Roomba S9 cleaning high pile carpet

That being said, it’s significantly pricier than even the 2nd most advanced Roomba, the Roomba i7+. While it does have a new body-style, greater suction, and a wider cleaning path, it is hard to say that this adds a significant amount of value to justify the higher cost.

Even the Roomba i7+ was able to operate at 99% overall cleaning performance, which just doesn’t leave a lot of room for improvement between the two models.

Roomba S9+ Specifications

SpecificationsRoomba S9+
TypeRobot
ManufactureriRobot
ModelRoomba S9+ (9550)
Width12.25"
Height3.5"
Weight8.15 lbs.
Floor TypeAll (indoor)
BatteryUnknown
Dust Bin CapacityUnknown
Imprint Smart MappingYes
Imprint LinkYes (pairs the S9+ vacuum with the braava M6 mop)
Self-Emptying (Advanced Base)Yes
Washable Dust Bin (on-board)Yes
Includes Digital WallYes
ReturnsVaries by retailer, other retailers will vary
Warranty1-Year limited
PriceCheck Price

Should You Buy the Roomba S9+?

For the best-of-the-best that Roomba has to offer, the Roomba S9+ is an amazing machine. While it is incredibly pricey, it also comes with the most advanced features on the robot vacuum market.

I would recommend the Roomba S9+ if you want the following in a robot:

  • Want a self-emptying dustbin: Aside from the Roomba i7+, the Roomba S9+ is one of the only other models on the market to offer a self-emptying dustbin. This feature can be useful if you want a “set it and forget it” approach to your robot.
  • Want a square front body: For the first time, iRobot has designed a square front robot with the Roomba S9+. While the body style certainly does remind us of comparable models to come from Neato Robotics, it’s a big change for Roomba. In addition to excellent edge cleaning, the square front body also allows for a wider cleaning path with longer brushrolls.
  • Want excellent cleaning performance: It scored 99% on all 3 of our floor cleaning tests. It offers incredible suction and that suction results in incredible cleaning performance. The Roomba S9+ is among the very best robots we have tested to date.

To learn more or to buy the Roomba S9+, you can check it out here.

Updates

  • March 27, 2020 – Updated our review with our 7 month test notes. Added a few pictures, removed comparison info (it is now located here), and fixed a few other minor issues.
  • October 3, 2019 – iRobot informed us that they call the new design a “square front” instead of “d-shaped”. They did not ask us to change it, but we felt we should as it feels more clear. iRobot also provided us with more information about the filter, which we felt was helpful so we decided to add it as well.
  • September 30, 2019 – Updated our review with our testing data, photographs, and refined information, opinions, and analysis. Quality score improved from 96% to 100%, which resulted in overall score improvement from 98% to 99%.
  • June 4, 2019 – Initial version of the page was published as a pre-test review.
Bleeding Edge Design & Performance
  • 100%
    Design - 100%
  • 99%
    Performance - 99%
  • 100%
    Quality - 100%
  • 100%
    Usability - 100%
  • 94%
    Value - 94%
99%

Summary

The iRobot Roomba S9+ is the most advanced robot vacuum ever built. It features a self-emptying dust bin, something only available in one other robot we’re aware of (the Roomba i7+). The recharge and resume feature allows it to continue charging itself up and cleaning until the job is done, no matter how big. Digital mapping, map control, edge cleaning, and more make this one of the best robot we’ve ever seen.

About Derek Hales

Derek HalesDerek Hales is the Founder and Editor-in-Chief of ModernCastle.com. He has been featured in Fast Company, Reader's Digest, Business Insider, Realtor.com, She Knows, and other major publications. Derek has a Bachelor's Degree in Business Administration from Kansas State University. Hales has been testing and reviewing products for the home since 2014.

Need Help? Ask Your Question Below

  1. Derek had a question for you I have several robot vacuums running in our house. I have an i7+ with the automated dust bin then a couple other cheaper ones.

    I was looking at maybe getting another iRobot so I could have more control and zones etc. I was wondering if you think the S9+ would be better to get or just get another i7+? I just dont know if the $200-$300 price difference is worth it and not sure so was hoping if you could let me know what you think and what you would do.

    Thanks

    Reply
    • In terms of control, the S9+ doesn’t have anything new vs. the i7+.

      The S9+ is basically the same as your i7+, except it has more suction power. If you have lots of high pile carpets, perhaps it’s worth it. But otherwise, no reason to not just add another i7+ and save the money, in my view.

    • Derek,
      Thanks do appreciate it.
      I kind of came to that same reasoning as well but then was not sure if I missed something or if really the new design made anything better or what not.
      I will probably just add another i7+ for the time being until maybe the s9+ comes down in price or a holiday sale or something.

    • My pleasure!

      I think that makes a lot of sense. i7+ is still an amazing vacuum in its own right. No need to spend extra given its performance relative to the S9+.

  2. I’ve been using the S9+ for about half a year. I’ve had a problem that surfaces about 20% of the time whereby it has trouble docking and will sometimes fail completely and sit helplessly not on the charging/emptying dock correctly. It will often try a few times before it gets it right when it does (the remaining amount of times). There doesn’t seem to be any rhyme or reason as to when it will dock correctly and when it won’t. Just tonight I noticed that two plastic pieces that help guide it (that are on the floor of the clean base) were worn down from attempts by the vacuum to dock.

    The store didn’t have any advice for me. Anyone else exhibiting this behavior?

    Reply
    • Hi Dovid,

      Thanks for sharing your experience.

      That is indeed very strange. I haven’t heard of an S9+ (or any Roomba for that matter) exhibiting this behavior thus far. Have you brought the problem to iRobot’s customer support? I expect they should be able to assist you more than the store you purchased it from.

  3. I received a new S9+ w/the dust bin and Brava m9. I find the s9+ to be very very noisy and with a scraping sound. It certainly gets into a lot more trouble than my old 500 series. I fully understand that the area must be robot friendly which it was for the 500 series but need to further tweak the floor since the s9 goes into places that the other one did not. It even goes in-between my kitchen island bar stools. It does not like my bathroom floor run…its rolls it up into the rollers and proceeded to make the rug bald by constantly brushing the same area…now for the other news…a few days in lots of S31 communication errors. It now stops on open ares with an 31 error. I am constantly babysitting (home due to Pandemic) the robot unlike my older robot that just seem to work every day without issue. Open call, they had me do the 3 reset. I even did a hard factory reset and lost my map. Ten minutes into the first run after reset, it stopped again in an open area with a S31 error. iRobot representative is schedule to check back with me in two days. The robot is still less than 30 days old. I am also worried about the very loud unusual noice it makes. I even lowered to suction to the lowest level but still keeps lots of noise. I do love the robot but it must work without me babysitting it.

    Reply
    • Sounds like there is some type of a defect with your unit. Glad to hear iRobot is going to fix it.

      As far as the noise goes, I will say that it is indeed louder than most. However, I think this is because it’s also the highest suction robot vacuum on the market (at least to the best of my knowledge).

      I would suggest you create keep out zones to keep it away from your bar stools, rugs, and other areas it can get stuck on. I did the same for mine and find I end up doing a lot less baby sitting.

  4. I’m looking to use this on two separate floors. On the second floor, is there a spare home base I can purchase (without the dustbin emptying function) for it to charge on? Will it work on some of the older iRobot charging stations?

    Reply
    • Unfortunately there is not. Only the new larger clean base (with the self empty dust bin) can charge the S9. The older style charging stations won’t work.

      However, you really don’t need a charging base upstairs. The S9+ can handle multiple floors in its memory map, so you can just drop it on each floor and let it clean, then put it back on the floor with the charger when done.

  5. Any issues with the notorious red error ring (error code 31)? Received a brand new unit and over the course of 48 hrs had 9 error codes. Unable to continue cleaning job, advised by iRobot to perform series of 3 reboots. Finally contacted seller only two days later and now returning it.

    Reply
    • That’s interesting. I have never experienced code 31. Sorry to hear you’re having so much trouble.

      Hopefully the replacement unit will resolve this issue.

  6. My first S9+ went dead after 2.5 months: always gave an internal communication failure. iRobot gave me an entirely new one. It is working so far. But sometimes it does miss some spots. But that seems a matter of training the robot sufficiently. I have the impression the software still leaves room for improvement as sometimes it still crawls illogically around. But overall it is indeed one of the best robotic cleaners around and I am happy with it. It is better than the wet-cleaner, the Braava M6 Jet which doesn’t seem to be able to go from room to room when there is a small door-step.

    Reply
    • Thanks so much for sharing your experience, Harvey! I’m glad the new S9+ you got seems to be working better.

  7. My only thought about the new brush design is that because it is wider, it should be able to cover the more area in any one pass. With the same 75 minute run-time between the two models, the s9+ should cover a greater area during each charge cycle than an i7+ would. This would in theory let it do the floor in fewer passes, shortening cleaning time, and reduce the number of cycles a battery is put through. May also positively impact s9 brush life as well, by reducing run time and spreading out the wear on a larger surface.

    Reply
    • That’s definitely true. The larger brushroll should help to increase overall efficiency. I didn’t think of that on our first pass through the specs.

      Thanks for bringing that to my attention!

  8. S9 vs I7.

    How does the shape matter? When you test it practically u will see both S9 and I7 has a limitation to clean the area on the opposite side of the side brush. The way how I7 works is that the opposite side get tackled when the Roomba changes the direction. So other than suction and design look there is not much difference between I7 and S9. Save your money and get I7 and u will not go wrong. I am 100 percent happy with the suction power and the vacuum task and why I have a dog too that stays with me. So go for I7 and save some $$$.

    Reply
    • I think you make a fair point.

      While the S9+ is incredibly impressive in terms of smart features, I’m not sure it’s going to be all that different in terms of raw cleaning power compared to the i7+.

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