Disposable vs permanent cat litter boxes: true cost

Quick heads-up before we get into the cost comparison: most litter boxes — disposable ones especially — are too small. Cats need a tray that's at least 1.5 times their body length to feel comfortable, and disposable boxes rarely hit that mark. Covered boxes have the same problem in reverse: tidier for you, but cats often avoid them because they feel trapped inside. So before the price question, let's make sure whatever you land on actually works for your cat. How many cats do you have, how big are they, and are you dealing with any litter box problems right now — avoidance, missing the sides, anything like that?

Good that she's using it without issues — that's the baseline you want to protect when you switch. On the cost question: disposable cardboard boxes typically run £2–4 each, so weekly that's £100–200 a year, and you're getting a new undersized box every seven days. A solid permanent tray costs £15–30 once, lasts years, and the only ongoing cost is litter. The maths isn't close. What litter are you using at the moment — clumping, non-clumping, something else?

That's a good routine — daily scooping and a weekly clean is exactly right. With clumping litter and that kind of maintenance, a permanent tray will last indefinitely. For a 4kg tabby I'd go with the Savic Senator 50 open tray. It's 51cm long, which comfortably clears the 1.5x body length rule for most medium cats, has a low front entry so she can walk in easily, and a high back and sides to contain litter scatter. It's around £18–22 on Amazon UK, so you'd recoup the cost inside a fortnight compared to what you're spending now. No lid — which is the right call for a cat who's currently happy with an open box. No need to introduce a variable that might put her off.

Yes — keep the transition simple. Put the new tray in exactly the same spot as the old one, add some of the used litter from the old box into the new one so it smells familiar, and don't switch both the box and the litter at the same time. Since her habits are solid right now, she'll almost certainly take to it within a day or two. Just keep the new tray clean and she won't have any reason to object.

Good choice — it's straightforward, the right size, and you'll stop throwing money away every week. One thing to bear in mind: if you ever add a second cat, the rule of thumb is one tray per cat plus one extra, so you'd want two trays at that point. For now, one Senator and your current routine will serve her well.