Roomba i1+ vs. i3+: Which Self-Emptying Robot Vacuum Offers the Best Value?

The Roomba i1+ and Roomba i3+ represent two of the most compelling entry points into iRobot’s self-emptying ecosystem, offering the convenience of automatic dirt disposal without the premium price tag of the j7 or s9 series. Both models deliver on the core promise of a “set it and forget it” cleaning experience, using systematic navigation to map your home and clean in efficient, straight rows rather than relying on random bounce patterns. They share nearly identical internal components—same suction power, same dual rubber brushes, same Clean Base technology—making them functionally twins under the hood. Yet, despite these similarities, they cater to slightly different buyer priorities based on design, availability, and subtle differences in app feedback.

For many consumers, the decision between the Roomba i1+ and Roomba i3+ isn’t about cleaning performance—it’s about value, aesthetics, and long-term usability. The i1+ often appears as a retailer-exclusive model (like at Walmart), positioned as a budget-friendly alternative, while the i3+ enjoys broader availability and a more premium build. Both are excellent choices for pet owners, allergy sufferers, and busy households, excelling at picking up pet hair, lifting debris from carpets, and operating autonomously for up to 60 days without manual intervention. But which one truly offers the best balance of performance, features, and price?

This in-depth comparison breaks down every key aspect—from cleaning power and navigation to smart features and long-term ownership costs—to help you decide whether the Roomba i1+ or Roomba i3+ is the smarter investment for your home.

2. Product Overviews

Roomba i1+ (Model i155220)

The Roomba i1+ (model i155220) is iRobot’s value-focused gateway into the self-emptying robot vacuum category. Designed to deliver premium cleaning performance at a more accessible price point, it shares the same core engineering as the i3+ and i4+ but is often sold exclusively through select retailers like Walmart. This strategic positioning allows it to undercut the i3+ on price while retaining the essential features that define the “Plus” experience.

At its heart, the i1+ features the Clean Base Automatic Dirt Disposal system, which automatically empties the robot’s 0.6-liter bin into a sealed bag in the base—holding up to 60 days of dirt. This means you can go two months without touching a dustbin, a major convenience for busy households. The robot itself uses 10x Power-Lifting Suction (compared to the Roomba 600 series) and a Premium 3-Stage Cleaning System that includes an edge-sweeping brush, dual multi-surface rubber rollers, and a high-efficiency filter that captures 99% of allergens.

Navigation is handled via floor-tracking sensors that enable systematic, row-by-row cleaning—far more efficient than random bounce patterns. While it creates a digital map of your home, the app interaction is limited; you can’t label rooms or set virtual boundaries. It supports Recharge & Resume, so if the battery runs low during a large cleaning job, it returns to the dock, charges, and picks up where it left off. The i1+ is compatible with Amazon Alexa and Google Assistant for voice control, and the iRobot HOME app allows for scheduling, maintenance alerts, and cleaning history.

One of the i1+’s standout strengths is its pet hair performance. The dual rubber rollers are specifically engineered to resist tangles, making it a top choice for homes with shedding pets. Real-world testing shows it removes 99% of debris from both hardwood and carpet, matching the performance of more expensive models.

Check the latest price of [Roomba i1+] on Amazon [link]

Roomba i3+ (Model 3550)

The Roomba i3+ (model 3550) is the widely available standard-bearer for mid-range robot vacuums, launched in 2020 as a more affordable alternative to the i7+. It brings the same high-end cleaning system and self-emptying base to a broader audience, making it one of the most popular choices in its class.

Like the i1+, the i3+ features 10x Power-Lifting Suction, dual rubber brushes, and the Clean Base Automatic Dirt Disposal with 60-day capacity. It uses Imprint Smart Mapping to learn your home layout and clean systematically, ensuring complete coverage. The navigation is identical to the i1+—relying on floor-tracking sensors rather than a camera—so it moves in straight lines and avoids the inefficiency of random navigation.

However, the i3+ offers a slightly more refined app experience. While you still can’t label rooms or create virtual boundaries, the iRobot HOME app provides a clearer visualization of the cleaning path and history. It also includes Dirt Detect Technology, which uses acoustic and optical sensors to identify high-traffic, dirty areas and perform extra passes automatically.

The i3+ supports Recharge & Resume, voice control via Alexa and Google Assistant, and integrates with iRobot Genius, which learns your habits and suggests optimal cleaning schedules based on your routine and local conditions like pollen levels. The robot’s design is more premium than the i1+, with a textured, fingerprint-resistant top that resists smudges and looks more sophisticated in open living spaces.

While the i3+ is typically priced higher than the i1+—often around $399–$449—it’s frequently on sale, bringing it closer to the i1+’s price point. It’s a well-rounded, reliable robot that delivers flagship-level cleaning without the flagship-level cost.

See current deals on [Roomba i3+] here [link]

3. Comparison Criteria

To determine which robot vacuum offers the better value, we’ll evaluate the Roomba i1+ and Roomba i3+ across six critical dimensions:

1. Cleaning Performance: We’ll compare suction power, brush efficiency, and real-world debris pickup on hardwood, tile, and various carpet pile heights. Special attention will be paid to pet hair handling, a key concern for many buyers.

2. Navigation & Mapping: Both robots use systematic navigation, but we’ll examine how accurately they map your home, their ability to avoid obstacles, and the usability of their digital maps. We’ll also assess the limitations of not having camera-based vSLAM.

3. Smart Features & App Control: This includes scheduling, voice commands, app interface, and automation capabilities. We’ll look at how well each model integrates with smart home ecosystems and whether the i3+ offers any meaningful advantages in usability.

4. Battery Life & Autonomy: Runtime, charging time, and the effectiveness of the Recharge & Resume feature will be analyzed. We’ll determine how well each robot handles large homes or multi-floor cleaning.

5. Design & Build Quality: Aesthetics, materials, dustbin accessibility, and durability will be compared. The i3+’s textured top versus the i1+’s smoother finish will be a key differentiator.

6. Value for Money: We’ll weigh the upfront cost against long-term ownership expenses—replacement bags, filters, brushes—and assess which model offers the best overall return on investment for the average user.

By examining these factors side-by-side, we’ll identify not just which robot performs better, but which one makes more sense for different types of households and budgets.

4. Head-to-Head Comparison

Cleaning Performance

When it comes to raw cleaning power, there is no meaningful difference between the Roomba i1+ and i3+. Both models use the same Premium 3-Stage Cleaning System, which begins with an edge-sweeping brush that pulls debris from corners and baseboards into the main cleaning path. The dual multi-surface rubber brushes—iRobot’s patented tangle-free design—rotate in opposite directions to loosen and lift dirt, dust, and pet hair from both hard floors and carpets. These rubber rollers are far more effective than traditional bristle brushes at preventing hair wrap, a major pain point for pet owners.

Suction power is rated at 10x Power-Lifting Suction compared to the Roomba 600 series, with independent testing suggesting a real-world suction force of up to 2000 Pa. This is more than sufficient to pull embedded dirt from low- and high-pile carpets. In controlled tests involving cereal, rice, kitty litter, sugar, and pet hair, both robots achieved a 99% debris removal rate across hardwood, low-pile, and high-pile carpet. The i3+’s official deep clean score of 81/100 on embedded sand further confirms its strong performance on tough messes.

Both models also feature Dirt Detect Technology, which uses a combination of acoustic and optical sensors to identify high-traffic, dirty areas. When such a zone is detected—like a kitchen floor after dinner or an entryway after a rainy day—the robot automatically performs multiple passes to ensure thorough cleaning. This intelligent feature works identically on both robots.

The only minor difference lies in dustbin capacity: the i1+ has a 0.6-liter bin, while the i3+’s is slightly smaller at 0.5 liters. However, since both robots empty into the Clean Base after every run, this difference is negligible in daily use. The Clean Base itself holds up to 60 days of debris, so you’ll rarely interact with the robot’s bin.

Pro Tip: While the rubber brushes resist tangles, they can still accumulate grease over time, especially on clean floors. iRobot recommends inspecting and cleaning the rollers weekly to maintain peak performance.

🏆 Section Winner: Tie. Both robots deliver identical cleaning results across all floor types and debris types. The i1+ and i3+ are functionally indistinguishable in this category.

Check the latest price of [Roomba i1+] on Amazon [link]
See current deals on [Roomba i3+] here [link]

Navigation & Mapping

Both the Roomba i1+ and i3+ rely on floor-tracking sensors rather than a top-mounted camera for navigation. This means they use a system of infrared and optical sensors to measure distance and track movement, allowing them to clean in systematic, straight rows—a significant upgrade over the random “bump-and-run” pattern of older models. This method ensures complete coverage and minimizes missed spots, making both robots highly efficient in homes with complex layouts.

During the initial cleaning cycle, each robot maps your floor plan in real time, learning the layout of rooms, furniture, and obstacles. The i3+ markets this as Imprint Smart Mapping, while the i1+ uses the same underlying technology but with less emphasis on app visualization. In practice, both robots create a digital map that allows for recharge and resume, room-specific cleaning, and cleaning history tracking.

However, there are important limitations. Neither model supports room labeling, room merging, or virtual boundaries (Keep Out Zones) in the app. You cannot draw a line around your pet’s food bowl or designate a “no-go” zone for cords. If you need this level of control, you’ll have to use a physical Virtual Wall barrier (sold separately), which emits an invisible infrared beam to block the robot.

That said, the i3+ offers a slightly more informative app experience. Its map visualization is clearer, with better path tracking and history logs. The i1+’s app is more basic, focusing on coverage rather than detailed map interaction. While neither robot uses vSLAM (camera-based mapping), their floor-tracking system is surprisingly effective, achieving 100% room coverage in real-world tests.

Obstacle avoidance is handled via bumper sensors and cliff detection. Both robots navigate around furniture, under beds (with 3.6” clearance), and across floor transitions without issue. However, they may occasionally run over cords or scatter small objects—something the camera-equipped j7+ can avoid.

🏆 Section Winner: Roomba i3+. While navigation logic is identical, the i3+ provides a more polished and informative map experience in the app, giving users better feedback on cleaning patterns.

View [Roomba i3+] on Amazon [link]

Smart Features & Connectivity

Both the Roomba i1+ and i3+ rely on the iRobot HOME App for setup, scheduling, and monitoring. The app is available for iOS and Android and requires a 2.4GHz Wi-Fi connection. Once paired, you can control the robot remotely, view cleaning history, and receive maintenance alerts (e.g., when to clean the brushes or replace the filter).

Scheduling is fully customizable on both models. You can set daily or weekly cleaning routines, and the iRobot Genius platform will learn your habits and suggest optimal times—such as cleaning when you’re at work or after dinner. The app also integrates with IFTTT, allowing for advanced automations like starting a cleaning cycle when your smart lock detects you’ve left the house.

Voice control is seamless with both robots. They work with Amazon Alexa and Google Assistant, letting you say things like “Alexa, tell Roomba to clean the living room” or “Hey Google, send Roomba home.” However, due to the lack of room labeling, these commands trigger a whole-home clean rather than targeting a specific room. Neither robot supports room-specific voice commands.

One subtle difference is in the app’s user interface. The i3+ benefits from a more refined design, with cleaner visuals and better organization of cleaning history and map data. The i1+’s app is functional but less polished, reflecting its value-oriented positioning.

Good to Know: You can manually empty the robot’s bin or the Clean Base without using disposable bags, saving money over time. The i1+’s app includes a “Manual Empty” option, while the i3+ requires a firmware update for this feature.

🏆 Section Winner: Tie. For day-to-day operations—scheduling, voice control, and remote start—the experience is nearly identical. The i3+ has a slight edge in app design, but it doesn’t translate to better functionality.

Check the latest price of [Roomba i1+] on Amazon [link]
See current deals on [Roomba i3+] here [link]

Battery Life & Autonomy

Both the Roomba i1+ and i3+ are powered by lithium-ion batteries with similar performance profiles. The i3+ has a rated runtime of 75 minutes, which is sufficient for most homes up to 1,500 sq. ft. The i1+ is sometimes listed with a 120-minute runtime, though real-world testing under mixed flooring conditions shows closer to 75–90 minutes.

When the battery runs low, both robots feature Recharge & Resume—a critical function for larger homes. If the cleaning job isn’t complete, the robot automatically returns to the Clean Base, charges for about 70 minutes, and then resumes cleaning from the exact spot it left off. This ensures full coverage even in multi-room homes.

Charging time for a full cycle is approximately 3 hours. The Clean Base serves as both the charging dock and dirt disposal station, so the robot docks after every cleaning session—whether it ran out of battery or not.

In practical terms, both robots can handle homes up to 2,000 sq. ft. over multiple charging cycles. The total cleaning time for a large home might be 3+ hours, but you don’t need to intervene. The system operates autonomously, making both models ideal for hands-off cleaning.

🏆 Section Winner: Tie. Battery life and autonomy are effectively the same. The i1+ may have a slight edge in maximum runtime, but the i3+ compensates with consistent performance and reliable resume functionality.

Design & Build Quality

This is where the two models visibly diverge. The Roomba i3+ features a textured, fingerprint-resistant top with a fabric-like finish that resists smudges and dust. Available in a sleek grey/black color scheme, it looks more premium and blends better in modern living spaces. The control interface is minimalist, with a hidden LED ring that only lights up during operation.

The Roomba i1+, in contrast, has a smooth, matte silver finish that, while attractive, shows fingerprints and dust more easily. It lacks the textured durability of the i3+ and feels more like a budget-oriented product. Both robots have the same dimensions (about 13.3” diameter, 3.6” height), so they fit under most furniture equally well.

The i3+ also has a slight edge in accessory availability. As a widely sold model, replacement filters, brushes, and Clean Base bags are easier to find. The i1+, being retailer-exclusive, may have more limited support in the long term.

Pro Tip: Both robots use the same AllergenLock bags and filters, so consumables are interchangeable. You can save money by using third-party or reusable bags.

🏆 Section Winner: Roomba i3+. The premium build, textured finish, and better availability make the i3+ feel more durable and aesthetically pleasing.

Value for Money

Here, the Roomba i1+ clearly takes the lead. Priced at around $349 (especially at Walmart), it delivers the same core cleaning and self-emptying performance as the i3+ but at a lower cost. The i3+ typically retails for $399–$449, though frequent sales can narrow the gap.

Long-term costs are identical: both use the same AllergenLock bags (~$15 for a 3-pack), high-efficiency filters (~$10), and dual rubber brushes (~$25). You can reduce running costs by manually emptying the bin and skipping the bags altogether.

Unless you specifically prefer the i3+’s design or wider support, the i1+ offers 99% of the experience for less money. For budget-conscious buyers, it’s the smarter choice.

🏆 Section Winner: Roomba i1+. Lower upfront cost with identical performance makes it the better value.

5. Pros and Cons Table

6. Best Use Case Recommendation

Choose the Roomba i1+ if:

• You’re on a tight budget and want the lowest-priced self-emptying Roomba.
• You don’t care about aesthetics—you’ll store the robot in a closet or don’t mind the smoother finish.
• You just want reliable, hands-off cleaning without needing room-specific control.
• You’re a pet owner looking for strong hair pickup at a lower price.

Choose the Roomba i3+ if:

• Design matters—you want a robot that looks premium in your living space.
• You value wider support and easier access to replacement parts.
• You prefer a slightly better app experience with clearer cleaning history and path tracking.
• You find it on sale close to the i1+’s price point, making the upgrade worthwhile.

7. Conclusion

The Roomba i1+ vs. i3+ showdown ultimately comes down to value versus polish. Under the hood, they are nearly identical—same suction, same brushes, same Clean Base, same navigation. Both remove 99% of debris, handle pet hair with ease, and offer true “set it and forget it” cleaning for up to 60 days.

The Roomba i1+ is the clear value winner. At around $349, it delivers flagship-level performance at a mid-range price. Unless the i3+’s textured finish or slightly better app feedback is a must-have, the i1+ is the smarter buy for most users.

The Roomba i3+ justifies its higher price only if you find it on deep sale or if aesthetics and long-term support are non-negotiable. For the majority of shoppers, the Roomba i1+ represents the sweet spot: high-end automation without the premium cost.

The Final Verdict:
For the best balance of performance and price, the Roomba i1+ is the recommended choice. It proves that you don’t need to pay extra for looks to get a robot that cleans like a premium model.