You’ve just spent twenty minutes washing bottles at the sink — rinsing, scrubbing with the tiny brush, fishing the teat out of the washing-up bowl — and now you need to sterilise them. You put them in the microwave steriliser, wait six minutes, burn your hand on the steam, and then remember you need another bottle in forty-five minutes because the baby feeds every two hours and you only own four bottles.
Sterilising is one of those baby tasks that’s not difficult but is relentlessly repetitive. The right steriliser makes it faster and less annoying. The wrong one adds steps, takes up worktop space you don’t have, and makes you wonder whether cold water tablets in a bucket would have been fine all along. Here’s what actually works.
In This Article
- Why You Need to Sterilise Bottles
- Electric Steam Sterilisers
- Microwave Steam Sterilisers
- UV Sterilisers
- Cold Water Sterilising
- Which Type Is Right for You
- Best Electric Steam Sterilisers 2026 UK
- Best Microwave Sterilisers 2026 UK
- Best UV Sterilisers 2026 UK
- Capacity and What Fits Inside
- Drying: The Overlooked Problem
- How Long Do Bottles Stay Sterile
- Frequently Asked Questions
Why You Need to Sterilise Bottles
Babies under 12 months have immature immune systems that can’t fight off bacteria the way an adult’s can. Milk residue left in bottles — even after washing — provides a perfect breeding ground for harmful bacteria including E. coli, salmonella, and staphylococcus. Sterilising kills these bacteria, reducing the risk of gastrointestinal infections that can cause serious illness in young babies.
The NHS recommends sterilising all feeding equipment until your baby is at least 12 months old. This includes bottles, teats, lids, breast pump parts, and anything else that comes into contact with milk.
Washing First, Then Sterilising
Sterilising doesn’t replace washing. You need to wash bottles in hot soapy water first, using a bottle brush to scrub inside the bottle and a teat brush for teats. Sterilising kills bacteria on a clean surface — it can’t penetrate dried-on milk residue. Wash thoroughly, then sterilise. Skipping the washing step is the most common mistake new parents make.
Electric Steam Sterilisers
Electric steam sterilisers are the most popular type in the UK. They’re standalone units that plug into the mains, heat water to create steam, and sterilise bottles in 6-12 minutes. You add water to the base, load the bottles, close the lid, and press a button.
How They Work
The heating element boils a measured amount of water, producing steam that fills the chamber and reaches every surface of the bottles and teats inside. The temperature reaches 100°C — enough to kill 99.9% of bacteria. The cycle completes automatically, and contents remain sterile inside the closed unit for a stated period (usually 24 hours if the lid isn’t opened).
Pros
- Capacity — most hold 6-8 bottles plus teats, lids, and small accessories
- Speed — 6-12 minutes depending on model
- Consistency — the machine controls time and temperature, so results are reliable every time
- No chemicals — just water
Cons
- Worktop space — they’re bulky. Expect something the size of a large slow cooker
- Limescale — hard water areas (most of south-east England) require regular descaling. White vinegar or citric acid every 2-4 weeks
- Steam burns — opening the lid releases a blast of hot steam. Always open away from you and wait 30 seconds before handling contents
- Bottles still wet — steam sterilising leaves bottles dripping wet. You either shake them out and use immediately, or buy a model with a drying function
Microwave Steam Sterilisers
Microwave sterilisers use the same principle as electric models — steam kills bacteria — but the microwave provides the heat instead of a built-in element. They’re essentially a sealed container with a measured water reservoir that you put in your microwave.
How They Work
Add water to the base, load bottles, close the container, and microwave for 3-8 minutes (depending on microwave wattage and model). The microwave heats the water to boiling, producing steam inside the sealed container. When done, leave to cool for 2-3 minutes before opening.
Pros
- Cheaper — £12-25 versus £50-150 for electric
- Faster — 3-5 minutes in most microwaves
- Portable — light, compact, works with any microwave (useful for holidays and grandparents’ houses)
- Less worktop clutter — stores inside the microwave or in a cupboard when not in use
Cons
- Capacity — most hold only 4 bottles. If you’re formula feeding exclusively, you’ll run multiple cycles per day
- Microwave required — obvious, but if your microwave is small or doesn’t have a turntable, some steriliser containers won’t fit or won’t heat evenly
- Metal parts — you cannot microwave metal. If your bottles have metal components (some anti-colic valve systems), microwave sterilising isn’t an option
- Hot handles — the container gets extremely hot. Use oven gloves to remove it
UV Sterilisers
UV sterilisers use ultraviolet light (specifically UV-C at 253.7nm wavelength) to destroy bacteria by damaging their DNA. The bottles sit in a chamber lined with UV-C bulbs that cycle for 3-10 minutes. No water, no steam, no chemicals.
How They Work
UV-C light penetrates bacterial cell walls and damages the DNA, preventing reproduction. The process is dry — bottles go in clean and come out dry and sterile. Many UV sterilisers include a drying function (warm air circulation) that removes residual moisture from washing before the UV cycle begins.
Pros
- Dry sterilising — no wet bottles to deal with. This alone is worth the premium for many parents
- No limescale — no water means no mineral buildup
- Quiet — no boiling, no steam. Just a gentle hum from the UV bulbs
- Longer sterility — many UV units maintain a sterile environment for up to 48 hours by running periodic short UV cycles
- Versatile — sterilises anything that fits: dummies, teething toys, breast pump parts, phone cases
Cons
- Expensive — £80-200 versus £15-80 for steam options
- Shadow problem — UV light only sterilises surfaces it directly reaches. Bottles must be positioned carefully so UV light enters from all angles. Overlapping bottles or poorly positioned items may have unsterilised patches
- Bulb replacement — UV-C bulbs degrade over time (typically 6-12 months of daily use) and need replacing. Replacement bulbs cost £10-25 depending on model
Cold Water Sterilising
The original method. You dissolve a sterilising tablet (Milton or similar) in cold water, submerge bottles for 15-30 minutes, and they’re done. No electricity, no equipment beyond a container large enough to hold your bottles.
When It Makes Sense
Cold water sterilising is the cheapest method (about £3-5 for 28 tablets), requires no equipment, and works anywhere — at home, at grandparents’, on holiday, camping. It’s the fallback method every parent should know even if they use a steam or UV steriliser daily. Keep a box of tablets in the changing bag for emergencies.
The Downsides
The solution needs replacing every 24 hours. Bottles smell faintly of the sterilising solution (a chlorine-like smell that some babies refuse). The 15-30 minute soak time is longer than steam or UV. And you need a container large enough to fully submerge bottles without air bubbles — any surface above the water line isn’t sterilised.
Which Type Is Right for You
Formula Feeding (8+ Bottles Per Day)
Electric steam steriliser with the largest capacity you can find (8-bottle models). You’ll run it 1-2 times per day. A drying function is worth the extra cost because wet bottles at 3am when you’re making a feed in the dark is miserable.
Combination Feeding (4-6 Bottles Per Day)
A microwave steriliser handles this volume in 1-2 cycles. Cheaper, faster, and takes up less space than an electric model. If worktop space is tight, this is the practical choice.
Breastfeeding with Occasional Bottles
A microwave steriliser or even cold water tablets. You’re sterilising 1-2 bottles and pump parts — you don’t need a large electric unit for this volume.
Budget-Limited
Cold water tablets and a clean bucket or large container. Total cost: about £8. It works perfectly well — it’s just slower and smellier than the alternatives.
Maximum Convenience
UV steriliser with integrated drying. Bottles go in wet, come out dry and sterile, and stay sterile for 48 hours. The most expensive option but eliminates the most annoyance.
Best Electric Steam Sterilisers 2026 UK
Tommee Tippee Advanced Electric Steriliser and Dryer (About £70-90)
The most popular electric steriliser in the UK, and for good reason. Holds 6 bottles (Tommee Tippee Closer to Nature bottles fit perfectly, but most brands fit), sterilises in 5 minutes, and the drying function removes moisture so bottles are ready to use immediately. The HEPA filter on the drying vent keeps the air clean during drying. Available from Boots, Amazon UK, Argos, and supermarkets.
Best for: Most formula-feeding parents. The drying function alone justifies the price.
Philips Avent 3-in-1 Electric Steriliser (About £55-75)
Adjustable size — configure it for 2, 4, or 6 bottles by stacking or removing sections. Sterilises in 6 minutes. No drying function, but the modular design means it takes up less space when you’re only sterilising a few items. Fits Avent and most other bottle brands. Available from Boots, Amazon UK, and John Lewis.
Best for: Parents who want flexibility and use varying numbers of bottles.
MAM Electric Steriliser and Express Bottle Warmer (About £80-100)
Dual-function unit that sterilises and warms bottles. Holds 6 MAM bottles (other brands may not fit as well due to MAM’s wide bottle shape). The 6-minute sterilising cycle and integrated bottle warmer make it a genuine space-saver for small kitchens. Available from Boots, Amazon UK, and Argos.
Best for: MAM bottle users who want an all-in-one unit.
Best Microwave Sterilisers 2026 UK
Tommee Tippee Microsteri Microwave Steriliser (About £15-20)
Holds 4 bottles, sterilises in 4-8 minutes depending on microwave wattage. Simple, cheap, effective. The clip-lock lid is secure and the handle stays cool enough to grip with care (though oven gloves are still wise). Available from Boots, Argos, Amazon UK, and supermarkets. Our baby bottle guide covers which bottles work best with this steriliser.
Best for: Best value microwave option.
Philips Avent Microwave Steriliser (About £18-25)
Slightly larger than the Tommee Tippee, holding 4 standard bottles or 2 wide-neck bottles plus accessories. Sterilises in 2 minutes at 1,100W. Contents stay sterile for 24 hours if the lid stays closed. Available from Boots, Amazon UK, and John Lewis.
Best for: Avent bottle users.
Best UV Sterilisers 2026 UK
59S UV Steriliser and Dryer (About £100-130)
The most popular UV steriliser in the UK baby market. Large capacity (8 bottles or equivalent), integrated drying function, and a 48-hour sterile storage mode that runs brief UV cycles every 2 hours to maintain sterility. The touch-screen controls are intuitive and the build quality feels premium. Available from Amazon UK.
Best for: Parents who want dry, ready-to-use bottles with minimal effort.
Bololo UV Steriliser (About £80-110)
A budget-friendly UV alternative with similar features to the 59S — drying function, multiple cycle options, and storage mode. Slightly smaller capacity (6 bottles). The drying function is effective but slower than the 59S. Available from Amazon UK. Good value if the 59S is out of budget.
Best for: Budget UV option.
Capacity and What Fits Inside
Bottle Compatibility
Not all sterilisers fit all bottles. Wide-neck bottles (MAM, Tommee Tippee) take up more space than narrow bottles (Philips Avent Classic). Check the manufacturer’s bottle compatibility list before buying. The safest bet: buy a steriliser from the same brand as your bottles. If you’re using anti-colic bottles with internal valve systems, check that all parts can be sterilised in your chosen method.
Beyond Bottles
Sterilisers also handle breast pump parts, dummies, teething toys, and sippy cup spouts. If you’re pumping and bottle-feeding, you’ll need space for flanges, valves, and connectors alongside the bottles. Electric and UV sterilisers with removable racks or adjustable shelves handle this best.
Drying: The Overlooked Problem
Steam sterilising leaves bottles soaking wet. Using a wet bottle immediately is fine — the water inside is sterile. But if you’re making up bottles in advance (following NHS guidelines on formula preparation), wet bottles can dilute the formula concentration. And picking up a dripping wet bottle at 4am while holding a screaming baby is no one’s idea of fun.
Solutions
- Sterilisers with drying functions — the Tommee Tippee Advanced and most UV sterilisers include powered drying. Worth the premium
- Air drying on a clean rack — place sterilised bottles upside-down on a clean drying rack. They’ll air dry in 15-20 minutes but are exposed to airborne bacteria during this time (the sterility window ends the moment you open the steriliser)
- Shake and use — shake out excess water and use immediately. The residual moisture is sterile and won’t harm the baby
How Long Do Bottles Stay Sterile
Inside a Closed Steriliser
- Electric steam — typically 24 hours if the lid stays closed
- Microwave steam — typically 24 hours if unopened
- UV with storage mode — up to 48 hours with periodic UV cycles
- Cold water solution — bottles stay sterile as long as they’re submerged (solution replaced every 24 hours)
Once Removed
The moment you take a bottle out of the steriliser, the sterility clock starts ticking. Airborne bacteria settle on exposed surfaces within minutes. Use the bottle within a reasonable time — there’s no strict guideline, but most health visitors suggest using sterilised bottles within a few hours of removal.
Practical Advice
Sterilise a full load in the evening. Use bottles from the steriliser throughout the night and next morning. Sterilise again in the afternoon for the evening and overnight feeds. Two cycles per day covers most formula-feeding schedules.
Frequently Asked Questions
Which is better, electric or microwave steriliser? Electric sterilisers hold more bottles, have consistent results, and some include drying functions. Microwave sterilisers are cheaper, faster, and more portable. For formula feeding (8+ bottles daily), electric is more practical. For combination feeding or occasional use, microwave is the better value choice.
Are UV sterilisers safe for baby bottles? Yes. UV-C sterilisation is used in hospitals and water treatment. The UV light doesn’t leave any residue on the bottles — it’s a physical process, not chemical. The key is positioning bottles correctly so UV light reaches all surfaces. Follow the manufacturer’s loading instructions to avoid shadow spots.
How often should I sterilise baby bottles? Before every use until your baby is 12 months old, per NHS guidance. Wash bottles in hot soapy water after each feed, then sterilise before the next use. In practice, most parents batch-sterilise — washing all bottles in the evening and sterilising a full load at once.
Can I sterilise bottles in boiling water instead? Yes — submerge bottles, teats, and lids in a rolling boil for 10 minutes. It works but has downsides: repeated boiling can damage teats and plastics faster than steam, it uses a large pan, and there’s a burn risk. Steam and UV are safer and more practical for daily use. Boiling is fine as a backup method.
Do I need to sterilise bottles if I use a dishwasher? A dishwasher cleans but doesn’t sterilise. Most dishwashers don’t reach the sustained temperatures needed to kill all bacteria. The NHS recommends sterilising separately even if you dishwash bottles first. Treat the dishwasher as the washing step, then sterilise afterwards.