Bags for the Cat Litter Box: Which Type Fits — and When You Need None

The three kinds of litter box bags

Liners are plastic bags stretched inside a plastic tray. You pour litter on top and lift the whole bag out on change day.

Sifting bags have holes, so clean litter falls through while clumps stay in the bag. They need a second bag underneath and they tear easily.

Disposal bags are what you put used litter or a used tray into before it goes in the bin. These are the only bags almost every household really needs.

How to choose the right size

Measure the tray's length, width and depth, and add the height of the rim. A liner needs about 10 cm extra on each side to fold over the edge. If it is too small it slips into the litter, and if it is too large it bunches up in the corners where cats dig through it.

Drawstring bags and bags with elastic edges stay in place better than flat bags. Thicker bags last longer, but no plastic bag is safe from claws.

Why the inside bag often causes more work

Cats dig down to the bottom of the tray. Once the liner tears, urine gets underneath it, which causes smell, and you end up washing the plastic tray anyway. Many cats also dislike the slippery, rustling plastic.

We compare this in detail in our article on litter box liners vs a disposable tray.

The bag-free option: a disposable tray

EcoPetBox is a ready-to-use disposable litter tray made from moulded fibre, with no PFAS, wax or plastic film. Use it with your usual litter, and when it is time for a change, the whole tray goes in a disposal bag and into general household waste or home compost. It breaks down in 3–6 months. Do not put it in paper recycling.

For one cat, a set of three trays lasts about a month, or up to two months if trays that are still in good condition are reused. Check each tray before reusing it.