Can You Sterilise Baby Bottles in Advance?
Yes, you can sterilise bottles in advance – and doing so is one of the most effective ways to make the bottle feeding routine less relentless. Here's how to do it properly.
How far in advance can you sterilise?
Sterilised bottles stay suitably sterile for up to 24 hours, provided they're stored correctly. That means you can sterilise a full batch at the start of the day (or the night before) and use them throughout without re-sterilising between feeds.
The key conditions:
- Keep bottles sealed and assembled (teat, collar, and cap all in place) after sterilising
- Store in a sealed steriliser, a sterile container, or fully assembled in the fridge
- Don't leave them open on a surface or drying rack|Use within 24 hours of the sterilising cycle completing
Batch sterilising: how to do it
Batch sterilising means running one cycle with a full load of bottles rather than sterilising bottle by bottle. It's the most time-efficient approach for parents running 6-10 bottles a day.
- Wash all bottles, teats, rings, and caps thoroughly before loading – sterilising doesn't clean, it kills bacteria on clean surfaces
- Load your steriliser (or all-in-one machine) to capacity
- Run the cycle
- Once done, either leave sealed in the steriliser or immediately assemble each bottle and store upright
- Take bottles out as needed throughout the day
For a standard electric steriliser holding 6-8 bottles, one morning batch typically covers most of a day's feeds. For newborns on 8-10 feeds, a second batch in the evening covers the overnight feeds.
Batch sterilising for night feeds
Night feeds are where batch sterilising pays off most. The last thing you want at 3am is to be waiting for a steriliser to finish a cycle.
A practical approach:
- Run a full batch before the last evening feed or just before you go to bed
- Keep the steriliser sealed or the assembled bottles in the fridge
- For night feeds, prepare the bottle from the pre-sterilised batch – just add milk, warm if needed, feed
- If you're using formula, the NHS recommends making feeds fresh rather than in advance – use a flask of hot water (at least 70°C) kept next to the cot, add powder, cool quickly, feed
This way, the bottle preparation step at 3am is 30 seconds, not 15 minutes.
Can you sterilise the night before?
Yes – as long as the bottles are used within 24 hours of sterilising and stored correctly (sealed or assembled in the fridge), sterilising the night before is perfectly safe.
Some parents find it easier to run the sterilising cycle while the kitchen is being tidied after dinner, so clean bottles are waiting in the morning.
Running a full batch in one cycle is easiest with a machine designed for it. The Bebello 4-in-1 holds up to 8 bottles per cycle and handles washing, sterilising, and drying automatically.
Frequently asked questions
How many bottles should I sterilise at once?
As many as your steriliser can handle in one cycle – there's no benefit to doing fewer. See our guide on how many bottles fit in a steriliser for more detail.
Can pre-made formula be stored in advance?
Yes, but only in the fridge (under 5°C) for up to 24 hours. Don't leave made-up formula at room temperature for more than 2 hours.
Is it safe to reuse a sterilised bottle if you decide not to use it for a feed?
Yes, as long as it hasn't been opened or contaminated. A sealed, assembled bottle stays sterile for up to 24 hours from sterilising, whether you used it or not.
Does the 24-hour clock reset if I put the bottle back in the steriliser?
Only if you run another sterilising cycle. Simply placing an open bottle back in the unit doesn't re-sterilise it.