How often should I completely change clumping litter?

Every three to four weeks for one cat, if you are scooping every day. Two cats sharing a box roughly halves that. Scooping is what buys you the weeks, not the brand on the bag.

Do I need to change non-clumping litter more often?

Yes. Non-clumping litter holds urine in the whole bed rather than in a clump you can lift, so the bed reaches its limit sooner and a full change is usually weekly.

Can I just top the box up instead of changing it?

Topping up replaces what you scooped out and is part of normal upkeep, but it does not reset a bed that is already saturated. Cornell puts it simply: change it often enough that it looks and smells dry and clean.

Should I bleach the box at every change?

No. Unscented dish soap and warm water is enough, and it avoids leaving a smell your cat may object to. Strong scented cleaners are a common reason a cat starts avoiding a freshly cleaned box.

Litter Box Upkeep

How Often to Fully Change Cat Litter

Scoop every day. Dump the whole box every three to four weeks for one cat on clumping litter, and about weekly on non-clumping. Add a cat and it comes round sooner. Those are the usual starting points, not rules. The box tells you the real answer, and there is a one-line test for it below.

7 min read•Updated Aug 22, 2026

The test that beats any schedule

Cornell Feline Health Center gives the standard vets use: litter should be changed often enough that it looks and smells dry and clean, and the more cats using the box, the more often that will be. Look at the box before you look at the calendar.

What a bag lasted in our testing

These are the runs we recorded: how long one bag kept a box usable with daily scooping, for a single-cat home and for a multi-cat home. A bag lasting seven weeks does not mean seven weeks without a full change; it means the bag covered that many weeks of scooping plus the refills in between.

Clumping litters

Litter	Type	One cat	Multi-cat
Dr. Elsey's Cat Attract	Clumping Clay	7 weeks	4.5 weeks
Dr. Elsey's Ultra	Clumping Clay	7 weeks	4.5 weeks
Boxiecat Premium	Premium Clumping Clay	7 weeks	4 weeks
World's Best Cat Litter	Corn Litter	6 weeks	4 weeks
Naturally Fresh Walnut	Walnut Shell	6 weeks	4 weeks
Catalyst Soft Wood	Soft Wood / Pine	5 weeks	3.5 weeks
Arm & Hammer HardBall	Fast-Clumping Clay	5 weeks	3.5 weeks
Arm & Hammer Super Scoop	Budget Clumping Clay	4.5 weeks	3 weeks
Fresh Step Scented	Scented Clumping Clay	4.5 weeks	3 weeks
Frisco by Chewy	Budget Clumping Clay	4 weeks	2.8 weeks
Purina Tidy Cats	Budget Clumping Clay	4 weeks	2.8 weeks
Tuft + Paw	Soy / Tofu	4 weeks	2.5 weeks

Pellets, crystals and the rest

None of these form a clump you can lift out whole, so the whole bed does the work and a full change comes round sooner.

Litter	Type	One cat	Multi-cat
Sustainably Yours	Natural Corn + Cassava	6 weeks	4 weeks
PrettyLitter	Silica Crystal	4 weeks	2.5 weeks
Arm & Hammer Clump & Seal	Scented Clumping Clay	5 weeks	3.5 weeks
Feline Pine	Pine Pellet	6 weeks	3.5 weeks
Ökocat Paper Pellet	Paper Pellet	3.5 weeks	2 weeks

Change it early if you see these

The box smells within an hour of a clean scoop.
Litter looks grey or darkened right through, not just around the clumps.
Fresh urine puddles instead of soaking in, because the granules are already full.
Your cat starts standing on the rim, or digs for a long time before settling.
A film of fine grit coats the bottom when you tip the box.

A full change, step by step

Scoop out everything solid first, so you are not throwing away usable litter.
Tip the rest into a bag, tie it, and put it in the household bin.
Wash the empty box with unscented dish soap and warm water. Skip bleach and skip anything perfumed.
Dry it completely. Refilling a damp box makes the next batch cake at the bottom.
Refill to the same depth you always use, and put the box back in the same spot.

Add a cat, shorten the gap

Every extra cat sharing a box brings the full change forward, and our own runs show it in the table above. Dr. Elsey's Cat Attract, the strongest clumper we have drop-tested, covered 7 weeks of single-cat use and 4.5 weeks once more than one cat was on it. The cheaper fix is usually another box rather than a different litter.

Litters that held up with more than one cat

ReviewCatLitter editorial teamUpdated Aug 22, 2026

The weeks quoted on this page are the runs recorded in our own product testing, one bag at a time, with daily scooping.

Editorial standards Testing methodology

Questions people ask

How often should I completely change clumping litter?: Every three to four weeks for one cat, if you are scooping every day. Two cats sharing a box roughly halves that. Scooping is what buys you the weeks, not the brand on the bag.
Do I need to change non-clumping litter more often?: Yes. Non-clumping litter holds urine in the whole bed rather than in a clump you can lift, so the bed reaches its limit sooner and a full change is usually weekly.
Can I just top the box up instead of changing it?: Topping up replaces what you scooped out and is part of normal upkeep, but it does not reset a bed that is already saturated. Cornell puts it simply: change it often enough that it looks and smells dry and clean.
Should I bleach the box at every change?: No. Unscented dish soap and warm water is enough, and it avoids leaving a smell your cat may object to. Strong scented cleaners are a common reason a cat starts avoiding a freshly cleaned box.