Litter & Litter Tech
Best Stainless Steel Litter Boxes (2026)
A steel box gives you no more room than plastic at the same size. What it gives you is a surface that does not hold the smell of the last two years.
Affiliate disclosure: we earn a commission if you buy through our links, at no extra cost to you. It never changes which product we rank first — here is how we're funded.
Everyone in this category says they tested twenty litter boxes. We have not tested any, and we say so. What we do instead: compile the published specs, read the manuals, and do the arithmetic on what this gear costs to run and how it behaves once there is more than one cat using it. Every spec is linked to the document it came from. Prices are checked daily — last verified November 12, 2026. Here is exactly how we pick.
Quick picks
Ranked on the published specs and the arithmetic below. Tap any row to jump to the full write-up. We have not tested these — here is exactly how we pick.
| # | Product | Best for | Score | Price |
|---|---|---|---|---|
| 1 | iPrimio Stainless Steel XL Litter Box, Open Pan A 23.5 by 15.5 inch stainless pan with a nonstick interior -- steel does not scratch the way plastic does, and scratches are where litter box odor lives. | A large cat, and a box that never absorbs odor | 8.2 | |
| 2 |  Henkelion Stainless Steel Litter Box with Lid, Medium The same 20 by 14.2 inch footprint the retired iPrimio medium had, in steel, with the enclosure still attached -- a standard-size box for a home where the XL will not fit. | Stainless steel in a smaller space | 7.6 | |
| 3 |  Frisco High-Sided Cat Litter Box, XL 24-in Publishes its interior floor dimensions, not just the outside -- which is the only honest way to compare litter boxes and is rare enough to be a reason to buy. | Sprayers, on a budget | 7.6 |
#ad Buy links are affiliate links. Prices come from a live daily check; where we have no verified price we say "check price" rather than print a stale one.
Every plastic litter box eventually smells even when it is clean. That is not the litter failing -- it is the pan.
What you are actually buying
A litter scoop drags grit across the floor of the box several times a day. Over months that leaves fine scratches in plastic, and those scratches hold urine residue below the level a cloth reaches. It is the same argument our fountain materials page makes about plastic water bowls, and it applies harder here because the medium is abrasive.
Steel does not scratch that way. So the honest framing of this category is: you are not buying more room or better odor control today, you are buying a box that will be the same in three years as it is now.
Floor area, steel against plastic
iPrimio Stainless XL: 23.5 x 15.5 = 364 square inches.
So Phresh open X-Large, plastic: 22.4 x 16.9 = 379 square inches -- about 15 square inches MORE floor, for a fraction of the price.
Henkelion Medium: 20 x 14.2 = 284 square inches.
So steel buys you nothing in floor area. Anyone telling you a steel box is roomier is comparing different sizes, not different materials.
What the three publish
| Product | Material | External floor | Wall |
|---|---|---|---|
| iPrimio Stainless XL | Stainless steel | 23.5" x 15.5" | 6" open pan |
| Henkelion Medium, with lid | Steel pan, ABS enclosure | 20" x 14.2" | 11.8" to the top of the enclosure |
| Frisco High-Sided XL | Plastic | 24" x 18" (internal floor 19.75" x 12.875") | 10" |
Manufacturers' and retailers' published figures. Only Frisco publishes an internal floor -- and it is 59 percent of the external footprint.
The picks
The iPrimio Stainless XL is the one to buy. It is the larger of the two steel boxes and the easiest to step into, now that iPrimio lists it as a flat 6 inch open pan rather than the pan-plus-enclosure it used to sell. Neither steel box publishes an internal floor, which is the specification we would most like to see.
The Henkelion medium exists for rooms where 23.5 inches will not fit. At 284 square inches it is a standard box, fine for an average cat and tight for a big one — and it is the one of the two that still comes with an enclosure, at 11.8 inches to the top of it. It took this slot in November 2026 when iPrimio's medium was discontinued; the footprint is identical, so the comparison above is unchanged.
The Frisco High-Sided XL is here as the plastic benchmark and as the honest alternative. It publishes its internal floor, which neither steel box does, and its 10 inch walls contain more than the iPrimio's flat 6 inch pan does. It will scratch. That is the trade, stated plainly.
Living with a steel box
- Put a mat under it. Steel on a hard floor transmits every dig. Our mat roundup covers sizing.
- Dry it after washing. Standing water and urine salts are what corrode any steel.
- Expect noise at first. Some cats are startled by the sound of their own digging in a metal pan, and a few need a week to settle.
- Keep the same litter. Change one thing at a time.
Who should not buy one
- Anyone with an arthritic or senior cat. Wall height rules it out -- our senior page covers 3 inch entries.
- Anyone whose current box is fine. A plastic pan that does not smell after washing is doing its job.
- Anyone who needs maximum floor for the money. Plastic wins outright.
- A household with a noise-sensitive cat.
The picks in full
Specs are the manufacturer's own, linked to the page they came from. Prices come from a live daily check; where we have no verified price we say so rather than print a stale one.
iPrimio Stainless Steel XL Litter Box, Open Pan
iPrimio · Stainless steel litter box · Our score 8.2/10
#ad Price as of November 12, 2026. Prices move; we check daily. How we're funded.
A 23.5 by 15.5 inch stainless pan with a nonstick interior -- steel does not scratch the way plastic does, and scratches are where litter box odor lives.
Published specs
| Footprint | 23.5" x 15.5" |
|---|---|
| Height | 6" (open pan; no enclosure on this listing) |
| Interior | Nonstick surface with rounded corners |
| Material | Stainless steel |
| Maker's claim | Never absorbs odor, rust or stains like plastic |
| Weight, empty | 4.01 lb |
| Interior floor | Not published |
| Warranty | None published |
23.5 x 15.5 = 364 square inches, slightly LESS than the plain open jumbo pan we list elsewhere at 22.4 x 16.9 = 379. So you are not buying more room -- you are buying a surface that stays smooth. Plastic pans pick up fine scratches from scooping, and those scratches hold urine residue that washing does not reach.
What the specs favor
- Stainless steel does not develop the scratches that trap odor in plastic
- Nonstick interior with rounded corners, so waste lifts rather than needing scrubbing
- Big enough footprint for a large cat
- Will not crack or go brittle with age
What they don't
- Open pan only -- iPrimio's detachable enclosure is no longer listed, so a high sprayer is not contained
- No interior floor figure published
- Steel is loud when litter is poured or a cat digs hard
- More expensive than plastic for the same floor area
- No warranty published
Your cat sprays high. A flat 6 inch wall is all this pan has now that the enclosure variant has gone, and a high-sided box is the one that contains it.
How it scores
Scores are our editorial weighting of the published specs above, not a test result. They are deliberately kept out of this page's structured data.
Henkelion Stainless Steel Litter Box with Lid, Medium
Henkelion · Stainless steel litter box · Our score 7.6/10
#ad Price as of November 12, 2026. Prices move; we check daily. How we're funded.
The same 20 by 14.2 inch footprint the retired iPrimio medium had, in steel, with the enclosure still attached -- a standard-size box for a home where the XL will not fit.
Published specs
| Dimensions | 20" L x 14.2" W x 11.8" H |
|---|---|
| Capacity | 26 liters (maker) |
| Material | Stainless steel pan with an ABS high-wall enclosure |
| Enclosure fixing | Reinforced plastic clasps; overlap seam stated to keep urine in |
| Included | Double-layer litter mat, scoop and scoop holder |
| Base | Four anti-slip pads |
| Interior floor | Not published |
| Warranty | None published |
20 x 14.2 = 284 square inches, about 22 percent less than the XL's 23.5 x 15.5 = 364. That is a normal box for an average cat and a tight one for a large cat, which is why the XL leads for big cats and the medium leads for small rooms. The footprint is unchanged from the iPrimio medium this slot used to hold, so the comparison still stands -- only the maker changed.
What the specs favor
- Steel pan surface that stays smooth and does not hold odor
- Fits where a 23.5 inch box will not, on the same footprint as the box it replaces
- Enclosure is included rather than a separate purchase
- Mat, scoop and scoop holder in the box
- Publishes a liter capacity, which almost nothing in this category does
What they don't
- 284 square inches is tight for a large cat
- The enclosure is ABS plastic, so only the pan is steel
- Interior floor not published
- Steel is noisy when a cat digs
- No warranty published
Your cat is large. The XL's extra 80 square inches is the difference between turning around and backing out.
How it scores
Scores are our editorial weighting of the published specs above, not a test result. They are deliberately kept out of this page's structured data.
Frisco High-Sided Cat Litter Box, XL 24-in
Frisco · Litter box · Our score 7.6/10
#ad Price as of November 12, 2026. Prices move; we check daily. How we're funded.
Publishes its interior floor dimensions, not just the outside -- which is the only honest way to compare litter boxes and is rare enough to be a reason to buy.
Published specs
| External dimensions | 24" L x 18" W x 10" H |
|---|---|
| Internal floor | 19.75" L x 12.875" W |
| Wall height | 10" |
| Litter type | Any |
Source: Chewy -- Frisco High-Sided Cat Litter Box XL 24-in listing
24 x 18 = 432 sq inches outside. Frisco publishes the interior floor as 19.75 x 12.875 = 254 sq inches. You lose 41 percent of the footprint to sloped walls -- which is exactly why comparing boxes on external dimensions misleads you.
What the specs favor
- Publishes internal floor dimensions, which almost no maker does
- 10-inch walls contain a standing sprayer
- Cheapest way to get past 250 square inches of usable floor
- Open top
What they don't
- Loses 41 percent of its footprint to sloped walls
- No scatter shield, so litter still leaves with the cat
- 10-inch walls are still a climb for an old cat
You are buying one box for three cats. 254 square inches of usable floor is a single-cat box being asked to do a household's work.
How it scores
Scores are our editorial weighting of the published specs above, not a test result. They are deliberately kept out of this page's structured data.
Common questions
Are stainless steel litter boxes worth it?
Do stainless steel litter boxes smell less?
Are metal litter boxes noisy?
Will a stainless steel box rust?
Is a steel box good for a senior cat?
Sources
- Amazon listing -- iPrimio Stainless Steel Cat Litter Box, Nonstick, XL 23.5" x 15.5" Open Pan (extra large open steel pan stated as built for big cats, smooth nonstick interior with rounded corners stated to rinse clean without scrubbing, published 23.5 x 15.5 x 6 in, 4.01 lb, maker states steel never absorbs odor, rust or stains like plastic; no interior floor figure and no warranty published)
- Amazon listing -- Henkelion Stainless Steel Cat Litter Box with Lid, model HK-STAINLESS-STEEL-LITTER-BOX-M-01 (published 20" L x 14.2" W x 11.8" H, 26 liter capacity, thick stainless steel pan with an ABS enclosed high-wall enclosure, reinforced plastic clasps and an overlap design stated to keep urine in the box, double-layer litter mat plus scoop and scoop holder included, four anti-slip pads; no interior floor figure and no warranty published)
- Chewy -- Frisco High-Sided Cat Litter Box XL 24-in listing
- Amazon -- So Phresh by Petco Open Cat Litter Box, Charcoal, X-Large listing (22.4 in L x 16.9 in W x 5.4 in H, open pan, plastic; no interior dimension or unit weight published)
- Ohio State University Indoor Pet Initiative -- Litter Boxes
Read next
- Best Litter Boxes for Large Cats (2026)
Manual litter boxes for big cats compared on published floor area, wall height and entry -- with the turn-around test that rules most boxes out.
- Best High Sided Litter Boxes (2026)
High-sided boxes compared on published wall height and floor, and how to tell a spraying problem from a digging one.
- Why Your Litter Box Smells (and How to Fix It)
Ammonia smell diagnosed cause-first: what it means, the free fixes that solve most cases, and the products worth buying only if those fail.
- Best Litter Boxes for Odor Control (2026)
Ranked on containment geometry rather than fragrance, with the covered-box trade-off stated plainly.
- How Often to Clean a Litter Box
The three separate cleaning jobs a litter box needs, on three different schedules, with the litter volume arithmetic per cat.