iRobot Roomba Plus 405 Combo
iRobot says the Roomba Plus 405 Combo climbs thresholds up to 16 mm (maker's number, step type not given), stands 4.2 in tall, and holds 75 days of dirt in its dock.
Refills cost about $46-$59 a year at Amazon prices checked November 2, 2026. The math.
Price as of November 2, 2026.
| Limit | Maker figure | Source |
|---|---|---|
| Threshold, up to | 16 mm (maker's number, step type not given) | homesupport.irobot.com |
| Height | 4.2 in | irobot.com |
| Dock holds dirt for | 75 days | irobot.com |
Not published by iRobot: a mop-lift height.
On our guides
- Pet hair, hardwood floors: passes 2 of 5 pet checks
- Roborock vs Roomba: passes 2 of 5 pet checks
Compare: Which Roomba to buy, Roomba alternatives that cost less, Roborock vs Roomba.
Maker figures, not our tests. Method.
Amazon listing
We link iRobot Roomba Plus 405 (G185) Combo Robot Vacuum & Mop with AutoWash Dock - Spinning Mop Pads, Self-Empties, P. Not linked:
- Part or refill: iRobot Roomba Plus 405 (G181) 2in1 Vacuum & Mop Robot with AutoWash Dock - Dual Spinning, Smart & Fa
- A different model: iRobot Roomba Plus 415 Robot Vacuum & Mop Combo, 2.8X More Suction, 90 Days Self-Emptying, Multifunc
What the maker says the iRobot Roomba Plus 405 Combo does
Mopping
It mops with two spinning pads. iRobot gives no mop-lift height. (maker page)
Mop upkeep
The dock washes the mop. The maker does not say the dock dries it, so check the pad does not stay damp. (maker page)
Obstacle avoidance
The maker does not say how it avoids cords, socks or pet messes. Pick up the floor before it runs.
Dock
Empties itself into a bag: about 75 days per bag. (maker page)
App and Wi-Fi
- Without the app: You can start a clean with the button on the robot, no app needed. (maker’s words)
- Without internet: iRobot says cleaning needs no app or Wi-Fi; it does not say schedules or maps run offline. (maker’s words)
Parts, warranty and repair
Warranty: 1 year (maker page). Where iRobot sells parts and how it handles repairs: iRobot parts, warranty and repair.
iRobot Roomba Plus 405 Combo refills: cost a year
Prices November 2, 2026.
| Part | Replace | Amazon pack | A year |
|---|---|---|---|
| Filter | every 3-6 months (maker) | $19.99 for 3 at Amazon | $13-$27 |
| Dock dirt disposal bag | up to 75 days per bag (maker) | $19.99 for 3 at Amazon | $32 |
Total for the refills we could price: $46-$59 a year.
More limits iRobot publishes
| Limit | Maker figure | Read from |
|---|---|---|
| Mop | two spinning pads | irobot.com |
| Self-emptying dock | yes | irobot.com |
| Warranty | 1 year | irobot.com |
| Washes its own mop | yes | irobot.com |
| Mapping | lidar | irobot.com |
Recall check (US and Canada): none found, November 2, 2026. iRobot has 1 other robot recall on file, for different models: iRobot Clean Base dock for the Roomba i7+.
Living with it
- Consumables
- The box ships with one spare AutoEmpty dust bag and one spare set of mop pads in addition to the ones installed on the robot and dock. irobot.com
- Battery
- iRobot's own Protect Plan terms describe the battery as a serviceable part: under that paid plan, iRobot will replace it if it no longer holds a charge per iRobot's own guidelines, once the standard warranty has ended. irobot.com
- Without the app or Wi-Fi
- Beyond the app and voice assistants, iRobot says a cleaning cycle can be started with no app or wifi at all by pressing the button on the robot itself. irobot.com
- Set-up
- iRobot says setup just requires placing the AutoWash dock on a hard floor at least 4 feet from any stairs before the robot maps the home through the app. irobot.com
- Maintenance
- iRobot's routine maintenance is wiping the bin, rinsing the dock's water tanks, cleaning the charging contacts and brushes, and swapping the filter every 3-6 months. irobot.com
- Warranty
- iRobot's Protect Plan page states that eligible iRobot products, this model included, carry a standard limited one-year manufacturer's warranty before any optional extended plan begins. irobot.com
- Known issue
- iRobot states the robot automatically steers around carpets whenever it is running in a combined vacuum+mop or mop-only mode, so it will skip rugs in those modes rather than mop them. irobot.com
- Camera and data
- iRobot says it encrypts stored data and limits access to it, and owners can delete their data before passing the robot on to a new owner. irobot.com
What long-term reviewers and owners report.
- Testers considered the new AutoWash dock a real upgrade over iRobot's previous self-washing docks, which had been poorly rated. vacuumwars.com
- Owners can vacuum and mop a mixed hard-floor-and-carpet home in a single run because the mop pads reliably lift whenever the robot senses carpet. vacuumwars.com
- The redesigned Roomba Home app gives owners real-time robot monitoring and more granular controls than iRobot's previous app. vacuumwars.com
- The 405 has no obstacle-avoidance cameras or sensors at all, a feature that's now common on competing robots in its price range. vacuumwars.com
- It only has one mopping water level, and testers found it leaves floors excessively wet. vacuumwars.com
- Owners are likely to run into app bugs; reviewers found the companion app consistently buggy during testing and noted other users reporting the same. vacuumwars.com
- In deep carpet-cleaning tests it recorded the worst embedded-dirt pickup score the reviewer has ever measured on a Roomba. vacuumwars.com
What independent testers found
Named testers’ published figures, not ours.
| What | Finding | Tester |
|---|---|---|
| Debris pickup | 58% debris pickup in the deep carpet-cleaning test, versus a 75% average across tested robots | Vacuum Wars |
| Noted | picked up only about half of the flattened pet hair on carpet, the lowest score the reviewer had recorded | Vacuum Wars |
| Noted | Only 17% of test hair tangled in the single roller brush in a 7-inch hair tangle evaluation, versus about 50% for iRobot's older dual-roller design | Vacuum Wars |
| Noted | Navigation efficiency of 0.76 square meters per minute, a record for a Roomba model but still only 30th overall among robots tested | Vacuum Wars |
| Noted | Scored 145 on the dried-on stain mopping test, far above the 93 category average | Vacuum Wars |
| Noted | Left 5.20g of water behind on the floor after mopping, about 5x the amount left by the average robot tested | Vacuum Wars |
- Vacuum Wars concluded the 405 fell short in several important tests: below-average suction and airflow, the poorest carpet deep-clean and pet-hair pickup results they had recorded at the time of testing, excessively wet mopping from its single water setting, no modern obstacle-avoidance sensors, and a still-buggy app. Vacuum Wars
- The reviewer ranked the 405 70th overall with a 1.66-star Vacuum Wars rating against a 2.8 average, despite having high hopes for iRobot's refreshed lineup going in. Vacuum Wars
Other iRobot models we track: Roomba 105 Combo, Roomba 105 Vac, Roomba 105X Combo, Roomba 115X Combo, Roomba 205 Combo, Roomba Combo 10 Max, Roomba Max 705 Combo, Roomba Max 715 Vac, Roomba Max 775 Combo, Roomba Max 875 Combo, Roomba Plus 415 Combo, Roomba Plus 415X Combo, Roomba Plus 505X Combo, Roomba Plus 515 Combo, Roomba Plus 575 Combo, Roomba Plus 678 Combo.