How to Reduce Odours in Hamster and Guinea Pig Cages: The Complete UK Guide

I'll be honest with you—the first time I kept hamsters as an adult, I thought I'd done everything right. Good-sized cage, quality food, the works. But within three days, my home office smelled like a farmyard. My partner gave me that look. You know the one.

That was five years ago. Since then, I've tested more small animal bedding products than I care to count, and I've learned that controlling cage odours isn't about masking smells with air fresheners (please don't do that—it can actually harm your pets). It's about understanding why cages smell and tackling the problem at its source.

Why Do Hamster and Guinea Pig Cages Smell?

Here's something that surprised me when I first researched this: hamsters and guinea pigs themselves are actually quite clean animals. The smell you're battling isn't coming from your pet—it's coming from urine breaking down into ammonia.

When your small pet wees in their bedding, bacteria get to work. The result? That sharp, eye-watering ammonia smell that can take over a room in days. The problem gets worse with:

• Poor ventilation – Plastic enclosures and glass aquariums trap odours because air doesn't circulate properly
• Inadequate bedding depth – Thin bedding saturates quickly and can't absorb enough moisture
• Infrequent spot cleaning – Leaving wet patches even for a day accelerates ammonia production
• The wrong bedding type – Some materials absorb liquid but not odour, creating a damp, smelly mess

Male guinea pigs deserve a special mention here. They scent-mark their territory constantly, and if you're cleaning too aggressively, they'll just mark more to re-establish their scent. I learned this the hard way—sometimes doing less is actually more effective.

Choosing the Best Bedding for Odour Control

Not all bedding is created equal when it comes to smell. After testing dozens of products over the years, here's what actually works.

Paper-Based Bedding: The Odour Control Champion

Paper bedding consistently outperforms other types for odour suppression. Carefresh, made from reclaimed paper fibres, has become something of an industry standard—and honestly, it's earned that reputation.

What makes paper bedding effective:

• Triple absorption – Carefresh absorbs three times more liquid than wood shavings, which means less wet bedding sitting around producing ammonia
• Odour-suppressing formula – The proprietary formula in products like Carefresh is designed to neutralise ammonia for up to 10 days
• 99% dust-free – This matters more than people realise. Dusty bedding irritates respiratory systems and makes the whole cage environment less pleasant

The downside? Cost. Carefresh isn't cheap, and if you've got multiple guinea pigs in a large C&C cage, you'll go through it quickly. I'll cover some strategies for managing costs later.

Wood Shavings: Affordable but Choose Carefully

Wood shavings remain popular because they're significantly cheaper than paper bedding. But here's the thing—not all wood shavings are safe.

Safe options:

• Kiln-dried pine – The drying process removes toxic aromatic oils (phenols) that are naturally present in pine
• Aspen shavings – Naturally low in phenols and safe for small pets

Avoid at all costs:

• Cedar – Contains toxic oils that can damage your pet's liver and respiratory system
• Non-kiln-dried pine – The aromatic oils that make it smell "nice" are actually harmful to small animals
• Sawdust – Too fine, causes respiratory issues

I should mention—whilst kiln-dried pine has decent odour absorption, it doesn't match paper bedding. You'll likely need to clean more frequently.

Hemp Bedding: The Underrated Choice

Aubiose and similar hemp beddings have a bit of a cult following among experienced guinea pig owners in the UK. It's super absorbent, virtually dust-free, and actually quite good for odour control.

The texture is different from paper or wood—more like chopped straw. Some pets love burrowing in it; others take time to adjust. Worth trying if you're finding paper bedding too expensive but want better performance than wood shavings.

Fleece Liners: Convenient, But...

I know fleece liners are trendy. They're reusable, look smart, and guinea pigs seem comfortable on them. But let me be blunt: they're not great for odour control.

Fleece wicks moisture through to an absorbent layer underneath, but urine smell tends to build up faster than with loose bedding. Most fleece users report needing to wash liners every 2-3 days to keep smells manageable. If you've got the laundry capacity and don't mind the extra washing, they're fine. Otherwise, stick with loose bedding.

The Ideal Cleaning Schedule for a Fresh Cage

This is where most people go wrong. Either they're cleaning too little (obvious problem) or—surprisingly—cleaning too much.

Daily: Spot Cleaning (5 Minutes)

Every day, remove:

• Wet bedding patches (most hamsters use a consistent toilet corner)
• Visible droppings, especially around food areas
• Soiled hay (if you use it)

Don't replace the removed bedding with fresh stuff every time. Just top up every few days. Why? Your pet needs to smell their own scent to feel secure. Constantly replacing bedding stresses them out and—in the case of male guinea pigs—triggers more scent marking.

Weekly: Partial Clean (15-20 Minutes)

Once a week, do a more thorough clean:

• Remove about a third of the bedding
• Keep some of the clean bedding that smells like your pet
• Add fresh bedding and mix it in
• Wipe down platforms, hides, and food bowls with pet-safe cleaner or diluted white vinegar

The key here is maintaining continuity. Your pet's home shouldn't smell completely different after every clean.

Monthly: Deep Clean (30-45 Minutes)

Once a month, do a full cage clean:

• Remove your pet to a secure carrier or playpen
• Take out all bedding
• Wash the entire cage with warm water and white vinegar (50/50 mix works well)
• Scrub any stubborn urine stains with a dedicated pet-safe enzyme cleaner
• Rinse thoroughly and dry completely before adding fresh bedding

A word of caution here: never use bleach or strong household cleaners. Even if you rinse well, residue can harm small pets. White vinegar is your friend—it neutralises odours without leaving harmful chemicals behind.

Cage Setup Tips That Actually Reduce Smell

Beyond bedding and cleaning, your cage setup makes a massive difference.

Ventilation Is Everything

If your cage is a glass tank or fully enclosed plastic habitat, you're fighting an uphill battle. These trap ammonia fumes and make odour control nearly impossible.

Better options:

• Wire cages with solid plastic bases (excellent airflow)
• C&C cages with coroplast bases (popular for guinea pigs)
• Tank toppers that add ventilation to aquarium-style setups

I've seen people try to fix ventilation by placing fans near cages. Don't—drafts can make your pet ill. You want gentle air circulation, not a wind tunnel.

Use Enough Bedding

Skimping on bedding is a false economy. You need at least:

• Hamsters: 15-20cm depth (they need to burrow anyway)
• Guinea pigs: 5-7cm depth across the whole cage
• Gerbils: 20-30cm depth (serious burrowers)

Deeper bedding means more absorption capacity and longer between full changes. A bag of Carefresh might seem expensive until you realise that proper depth actually makes it last longer because you're only replacing sections rather than the whole lot.

Create a Designated Toilet Area

Most small pets naturally pick a corner for their business. Encourage this by:

• Placing a small litter tray in their preferred corner
• Using a different substrate in the tray (paper pellets work well)
• Spot-cleaning this area daily

This concentrates the smell in one manageable area rather than spreading it throughout the cage. Some owners even litter-train their guinea pigs and hamsters—it takes patience but can dramatically reduce overall cage odour.

How Carefresh Bedding Tackles Odours

I've mentioned Carefresh several times, so let me explain why it's become my go-to recommendation for UK pet owners concerned about smell.

The Science Behind It

Carefresh uses what they call an "Odor Stop Formula"—a proprietary additive that suppresses ammonia. The exact composition isn't public, but the company confirms the additives are approved for use in drinking water treatment and tested for animal safety.

What this means in practice: fresh Carefresh in a properly ventilated cage with daily spot-cleaning genuinely can go 7-10 days without smelling offensive. I've tested this myself multiple times.

Carefresh Product Range

The range available in the UK includes:

• Carefresh Natural – The standard brown paper bedding
• Carefresh White – Same material, bleached white (some owners prefer it for spotting wet patches)
• Carefresh Confetti – Coloured variety, popular with kids
• Carefresh Complete – Premium version with enhanced odour control

All perform similarly for odour. Choose based on appearance preference or price.

Is Carefresh Worth the Cost?

Here's my honest take: Carefresh costs roughly 2-3 times more than basic wood shavings. But consider this:

• You can go longer between full changes
• The ammonia suppression is genuinely superior
• Less frequent cleaning means less stress for your pet
• Your home smells significantly better

For me, that trade-off is worth it. But if budget is tight, using Carefresh only in high-traffic areas (toilet corners, favourite sleeping spots) and cheaper bedding elsewhere is a reasonable compromise.

Paper Bedding vs Wood Shavings: Which Controls Odour Better?

Let me give you the straight comparison I wish I'd had when starting out.

The verdict: Paper bedding wins on odour control. Wood shavings win on price. If smell is your primary concern, paper bedding is worth the investment.

Common Mistakes That Make Cages Smell Worse

After years of testing and speaking with other pet owners, here are the mistakes I see repeatedly.

Using Scented Products

Air fresheners, scented bedding, perfumed sprays—they might make your room smell nice to human noses, but they're actively harmful to small pets. Hamsters and guinea pigs have extremely sensitive respiratory systems. Those chemical fragrances can cause:

• Respiratory irritation
• Eye problems
• Allergic reactions
• Chronic stress

If your pet's cage smells bad enough to need masking, the solution is better bedding and more frequent cleaning—not covering up the problem.

Overcleaning

Controversial opinion: some people clean too much. If you're doing a full bedding change twice a week and your guinea pig is constantly scent-marking, you're caught in a cycle. The more you remove their scent, the more they'll produce.

For most setups, weekly partial cleans and monthly deep cleans are sufficient. Let your nose guide you—if it doesn't smell bad, don't fix it.

Ignoring the Cage Itself

Plastic and metal absorb odours over time. Even with fresh bedding, an old cage can smell because urine has seeped into scratches and joins. If your cage smells despite doing everything right, it might be time for a new one.

Inadequate Hay Management

Guinea pigs need unlimited hay, but hay that's been weed on smells dreadful. Solutions:

• Use hay racks to keep hay off the floor
• Place cardboard layers under hay areas and replace them regularly
• Remove soiled hay daily

Where to Buy Quality Small Animal Bedding in the UK

Finding good bedding at reasonable prices takes a bit of shopping around.

Supermarkets:

Major supermarkets stock basic small animal supplies including bedding. Selection is limited but convenient for top-ups.

Pet Shops:

Pets at Home and independent pet shops carry the widest range. Pets at Home often has multibuys on Carefresh that bring the price down significantly.

Online:

Amazon, Zooplus, and specialist small pet retailers often have the best prices, especially for bulk purchases. Watch for delivery costs eating into savings though.

Farm Shops:

For wood shavings and hemp bedding, agricultural suppliers are often cheapest. Aubiose (hemp) is widely available at horse supply shops at much better prices than pet-branded versions.

Frequently Asked Questions

How often should you change hamster bedding?

The standard advice is a full change every 1-2 weeks, but this varies depending on cage size, bedding type, and individual pet habits. With good paper bedding like Carefresh and daily spot-cleaning of wet areas, many owners find they can go 7-10 days between full changes. The key is using your nose—if it starts smelling noticeably of ammonia, it's time for a change regardless of your schedule.

Do hamster cages smell bad?

Not if properly maintained. Hamsters themselves are clean animals that groom regularly. Cage odour comes from urine breaking down into ammonia, not from the hamster itself. With appropriate bedding, adequate ventilation, and regular spot-cleaning, a hamster cage shouldn't smell offensive. If yours does, it's usually a sign that something in your setup needs adjusting.

Why does my hamster cage smell even after cleaning?

This typically happens for a few reasons. First, the cage material itself may have absorbed odours—plastic and scratched surfaces are notorious for this. Try cleaning with a 50/50 white vinegar solution and scrubbing joins and corners thoroughly. Second, you might be using bedding with poor odour-control properties. Third, inadequate ventilation traps ammonia even when bedding is fresh. Finally, if your hamster has a health issue causing excessive or strong-smelling urine, a vet visit might be needed.

How can I make my hamster cage smell better?

Focus on prevention rather than masking. Use high-quality paper bedding like Carefresh that actively suppresses ammonia. Spot-clean the toilet area daily—this takes just minutes but makes a huge difference. Ensure your cage has good airflow (avoid fully enclosed plastic habitats). Use enough bedding depth so moisture is absorbed rather than pooling. And resist the temptation to use air fresheners or scented products, which can harm your pet.

Is Carefresh bedding worth the extra cost?

For odour control specifically, yes. Carefresh absorbs three times more liquid than wood shavings and includes an ammonia-suppressing formula that's genuinely effective. While it costs more upfront, you typically need to do full changes less frequently, and your home will smell noticeably better. If budget is a concern, consider using Carefresh in high-traffic areas (toilet corners, sleeping spots) and cheaper bedding elsewhere as a compromise.

What is the best bedding for guinea pigs to reduce smell?

Paper-based bedding like Carefresh consistently ranks highest for guinea pig odour control due to superior absorbency and ammonia suppression. Hemp bedding (Aubiose) is a good runner-up—highly absorbent and cheaper than paper. Kiln-dried pine shavings are a budget option but require more frequent changing. Avoid fleece liners if smell is your main concern, as they tend to develop odours faster than loose bedding options.

How do you keep a guinea pig cage from smelling?

Establish a consistent routine: daily spot-cleaning of toilet areas and soiled hay, weekly partial bedding changes, and monthly deep cleans with white vinegar. Use absorbent bedding at adequate depth (5-7cm minimum). Ensure proper ventilation—C&C cages or wire cages with solid bases are ideal. Create a designated toilet area with a small litter tray. And for male guinea pigs especially, avoid over-cleaning, which triggers more scent marking.

Final Thoughts

Managing small pet cage odours isn't complicated, but it does require consistency. The right bedding makes the biggest single difference—I'd recommend starting with Carefresh or similar paper bedding if you haven't tried it. Combine that with daily spot-cleaning, proper ventilation, and a sensible cage setup, and you can absolutely keep hamsters or guinea pigs without your home smelling like a pet shop.

One last thing: if you've done everything right and your pet's cage still smells unusually strong, consider a vet check. Changes in urine smell or volume can indicate health issues that need attention.

Your pets deserve a clean, comfortable home—and you deserve a house that doesn't make visitors wrinkle their noses. With the approach outlined here, you can have both.