Affordable enzyme cleaner for multiple cats

Three rescue cats means you're going through cleaner fast, so cost-per-litre matters. The only products that permanently eliminate pet odours are enzyme-based cleaners — anything else just masks the smell, which means your cats will keep returning to the same spots because they can still detect it. To point you to the best value option: are you dealing with carpet, hard floors, or sofas? And are these mostly urine stains, or a mix — and are they fresh or set in?

That's really common with rescues settling in — it usually settles down once they feel secure. For set-in urine on carpet you need an enzyme cleaner that can soak down to the underlay, because that's where the smell is coming from. Fresh stains are easier, but the older ones need a decent dwell time — at least 10 minutes before blotting. What I'd want to know before recommending: are you buying refills regularly, or would a large ready-to-use bottle work better for you?

In that case, Simple Solution Cat Stain and Odour Remover in the 4-litre size is the one I'd go for. It's a proper enzyme-based formula specifically designed for cat urine — not a general pet cleaner — and the 4L bottle brings the cost-per-litre right down compared to the smaller sizes. It works on both fresh and set-in stains on carpet. For the older patches, soak the area generously, cover it with a damp cloth to stop it drying out too fast, and give it 10 to 15 minutes before blotting. You may need two treatments on anything that's been there a while. It's widely available on Amazon UK and consistently one of the better-value options for high-volume use.

If you use enough of it and let the enzymes do their job, yes — it destroys the uric acid crystals that cause the smell rather than covering them up, which is why enzyme cleaners are the only thing that actually breaks the return-to-spot habit. The key mistakes people make are using too little product and not leaving it long enough. On set-in stains, don't be stingy — you need to saturate the same area the urine reached. Once it's fully dry and the smell is gone to you, it should be gone to them too.

Yes — avoid anything containing bleach or strong disinfectants on the same area. They don't neutralise the uric acid, and bleach actually makes cat urine smell worse by reacting with the ammonia. Also don't use steam cleaners on urine stains before treating with the enzyme cleaner — the heat sets the proteins into the carpet fibres and makes it harder for the enzymes to break them down. Treat first, let it fully dry, then steam if you want to freshen the carpet afterwards.