Can You Mix Different Types of Cat Litter?

Sometimes yes, sometimes no — and the difference comes down to granule size, clumping, and where the tray lives.

Owners mix litters for sensible reasons. To soften a transition. To stretch a premium bag. To coax a picky cat toward something new, or simply to see whether two good litters make a better one.

The honest answer is that some combinations work well and others quietly fail. What separates them is not brand loyalty but physics — granule size, clumping behaviour, and how the two materials share moisture.

Why people mix

The most common reason is transition. Moving a cat to a new litter works best gradually, and a shifting mix of old and new is the method itself — we cover the full approach in our guide to switching to plant-based litter.

The second reason is cost. Stretching a premium litter with a cheaper one is common practice, and it can be perfectly reasonable — provided the two litters are physically compatible, which is what the rest of this guide is about.

The third reason is performance, pairing one litter's strengths with another's. And the last is the cat: a tray they have gone cold on, and an owner searching for the version they will accept.

What mixes well

Two clumping litters of similar granule size behave predictably together. Plant with plant is the easiest pairing of all — tofu and cassava, for instance, mix happily through a transition because they clump the same way and weigh about the same, which is why the gradual method between them is so painless.

Plant with mineral can work well too. Mineral granules absorb quickly and anchor a clump; starch granules bind it and hold the shape. The pairing is complementary rather than competitive, which is exactly why blended litters exist as finished products.

If you do blend at home, treat it like a recipe rather than a topple. Mix thoroughly on the pour so the tray is uniform from the first dig, and keep the ratio consistent from bag to bag — a cat's footing should feel the same this week as it did last week.

Litters mix well when they agree on the basics — granule size, and the will to clump.

What struggles

Clumping with non-clumping is the classic mismatch. The non-clumping fraction sits inside every forming clump and interrupts the bond, so clumps come out soft and break apart on the scoop. You lose the main benefit of both bags.

Very different granule sizes disagree in a quieter way. With daily digging, larger pieces ride to the surface while fine granules settle beneath them, and the tray separates into layers. Moisture then takes uneven paths on the way down, and clumps form patchy instead of tight.

Over a two-week transition this barely matters. As a permanent arrangement, a blend of coarse and fine will keep re-sorting itself, so if you want a lasting mix, choose two litters whose granules could pass for siblings.

Crystal litters paired with clumping litters split the job in two. Crystals work by drying waste out; clumping litter works by sealing it in, and each absorbs moisture the other needs to do its work. Neither material is flawed — the two strategies simply conflict in one tray.

The picky cat problem

Fussiness about litter is usually fussiness about texture. Paws are sensitive instruments, and a cat objecting to a tray is far more often objecting to how it feels underfoot than to what it is made of. Fine, sandy textures are the ones cats gravitate to most often.

If you are mixing to please a picky cat, consider not mixing at all. A blend hides the signal. Run two trays side by side instead — the familiar litter in one, the candidate in the other — and let your cat vote with their paws.

Keep the test fair. Same tray style, same spot, same depth of around seven to eight centimetres in each, so that texture is the only thing being judged. Change one variable at a time and the answer arrives faster.

The result is usually clear within a week. If the finer tray wins, you have learned something a blended tray could never tell you.

Automatic litter boxes change the rules

A machine is a stricter judge than a scoop. Its sieve is sized to one granule specification and its sensors are calibrated to one density, so a mix of sizes confuses the sorting — clean litter lost to the waste drawer, or waste returned to the bed.

This is why we built Terra as a measured blend rather than suggesting owners pour their own. It is a naturally sourced pairing of 50% cassava and 50% mineral, with granule size and weight tuned so rakes sift cleanly and sensors read true.

If your box is automatic, mix nothing. Use one litter with one specification, and leave the blending to the people with the instruments.

The short answer

So yes, with conditions. Match the fundamentals — similar granule size, both clumping — and a mix behaves like one litter. Ignore them and the tray will tell you quickly.

And if the mixing you are doing is really a transition in disguise, go gradually, keep everything else still, and let your cat set the pace. That method works between any two litters that clump, and it has yet to be improved on.