I have two cats. Miso is 13 lbs and long-bodied. His brother is smaller but makes up for it in volume. When I started shopping for an automatic litter box, I quickly discovered that most of the “best of” lists were written by people who apparently have dainty little cats that weigh 8 lbs and delicately use the facilities once a day. Not helpful.
If you’ve got a big cat — a Maine Coon, a Ragdoll, a chunky domestic shorthair who’s just built that way — you already know the problem. Entry holes too small. Globes too narrow. Weight sensors that freak out because your cat is technically past their “limit.” Here’s what actually works.
What “Large Cat” Actually Means When You’re Shopping
Large cats are generally 13 lbs and up — though a fit, muscular Maine Coon male can hit 18–22 lbs and be perfectly healthy. The issues you’re trying to avoid aren’t just about weight. It’s body length, turning radius inside the globe, and whether your cat feels comfortable enough to actually use the thing. A cat that feels cramped will find somewhere else to go. You don’t want to discover that at 2am.
Three things to look for: entry opening at least 8.5 inches diameter for big cats (9+ inches is better), enough interior depth for a full turn, and a weight sensor rated above your cat’s actual weight with some margin. Some mid-range boxes cap at 12–15 lbs. If your cat is right at that edge, the sensor false-triggers — cycling while the cat is still inside. That’s a safety issue, not just an annoyance.
And waste capacity matters more with large cats. More cat, more waste, faster drawer fills. What empties every ten days for a 9 lb cat might need attention every four days for a 17 lb Maine Coon.
| Box | Entry Opening | Weight Limit | Waste Drawer | Smart App | Price |
|---|---|---|---|---|---|
| Litter-Robot 4 | 10.25 in | 20+ lbs | ⭐ Largest | ✅ | ~$699 |
| Leo’s Loo Too | 9 in | ~25 lbs | Medium | ✅ | ~$420 |
| PetSafe ScoopFree | Open top | No limit | Disposable tray | ✅ (Crystal Pro) | ~$160 |
The Best Automatic Litter Boxes for Large Cats
1. Litter-Robot 4 — Best All-Round for Large Cats
The globe opening on the Litter-Robot 4 is about 10.25 inches. That’s wide enough for most large cats to walk in without any awkward squeezing. I’ve watched Miso use ours — he walks straight in, turns around, does his thing, walks out. No hesitation. The interior is genuinely roomy.
The weight sensor handles cats up to around 20+ lbs without issue, which covers the vast majority of large breeds. And the waste drawer — which is the spec that matters most for big cats — is the largest in its category. Single large cat: you’re looking at 7–10 days between empties. That’s actually manageable.
It’s $699. I know. But for large cats specifically, the Litter-Robot earns its price more than it does for average-sized cats. The size and reliability advantages are more meaningful when you’ve got a big animal using it heavily every day.
2. Leo’s Loo Too — Best Value if Your Cat Is Under 18 lbs
The Leo’s Loo Too has a globe opening of around 9 inches. Fine for most large cats. If your cat is 13–17 lbs with a normal build, you’ll very likely be fine. If you have one of those enormous long-bodied Maine Coons pushing 20 lbs — measure carefully and maybe check some owner reviews from people with similarly-sized cats before you buy.
At $400–$450, the price-to-feature ratio is strong. The app is excellent, the active deodorizer helps with the larger deposits big cats tend to leave, and the weight sensor supports cats up to around 25 lbs. For one large cat, it handles the job well. Two large cats starts to push the waste drawer — you’ll be emptying every 3–4 days instead of 7.
3. PetSafe ScoopFree Crystal Pro — Best if Your Cat Rejects Enclosed Boxes
Here’s the thing about enclosed globe boxes: some cats just won’t go in them. Anxious cats, elderly cats, and some large cats that feel claustrophobic inside a globe will flat-out refuse. If you’ve already tried a globe box and your cat voted no with their feet — the ScoopFree is your answer.
The open-top rake design means no enclosure at all. Big cats walk straight in like it’s a normal litter box, because it essentially is, just one that rakes itself. Crystal litter is genuinely excellent for odor control even without a lid. The tradeoff is disposable trays — about $20–$25 each, lasting 20–25 days per cat. For one large cat that’s roughly $300/year in trays. Factor that in.
4. Litter-Robot 3 Connect (Refurbished) — Budget Option That Still Works
The previous generation, now often available refurbished from Whisker at $350–$450. Globe opening is around 10 inches — slightly smaller than the 4, still fine for most large cats. Waste drawer is smaller than the 4. But you get Litter-Robot’s build quality and support at a lower price point. If the 4 is out of budget, this is worth considering. Buy direct from Whisker for the warranty.
What to Avoid With Large Cats
Most budget globe boxes (under $150) have openings of 7–7.5 inches. A large Maine Coon won’t fit comfortably. If your cat squeezes in and feels cramped, they’ll stop using it within a week.
Watch out for weight sensor limits too. Marketing specs sometimes say “up to 15 lbs” — which sounds fine until you realize your cat is 14.8 lbs and the sensor is triggering during use. Check user reviews specifically from owners of large cats before buying anything under $300.
And multi-cat homes with two large cats need to think hard about waste drawer capacity. It fills faster than the marketing implies. Do the math based on your actual cats before assuming any single box will cover it comfortably.
My Pick for Most People
One large cat under 18 lbs: Leo’s Loo Too. Saves you $250 over the Litter-Robot 4 and performs comparably in daily use. The entry opening is fine, the waste capacity handles one cat well, and the app is genuinely good.
Two large cats, or a single cat over 18 lbs, or you just want the most reliable option with good support: Litter-Robot 4. The larger opening, bigger drawer, and Whisker’s track record justify the price for this use case specifically.
Cat that won’t go near a globe: PetSafe ScoopFree Crystal Pro. Accept the tray cost as the price of keeping the peace. It’s worth it.
One last thing — your cat’s comfort with the box matters more than any spec I can give you. The most capable automatic litter box in the world is worthless if your cat decides they don’t trust it. Give them time to adjust (2–3 weeks is normal), and don’t move the old box until they’re consistently using the new one.
