Can You Put a Stainless Steel Water Bottle in the Freezer?
Not if it has a vacuum wall: freezing a vacuum-insulated stainless steel bottle can stress the seal and let air into the gap, so drinks stop staying hot or cold. Use this manufacturer care guide for which bottles can be frozen and safer ways to get an ice-cold drink.
By Feng, Head of After-Sales Service & Online Marketing Lead
No. A stainless steel water bottle in the freezer is at risk if the bottle is vacuum insulated. BG Drinkware, a drinkware manufacturer in Yongkang, China, tells its customers in advance to keep double-wall vacuum bottles out of the freezer, and out of the refrigerator as well. The same rule applies to double-wall titanium bottles. BG Drinkware’s standard vacuum bottle has a 304 stainless steel inner wall and a 201 outer wall, with a sealed vacuum gap between them. That gap blocks the cold, so the drink inside cannot cool effectively. In the freezer, the temperature difference may also harden the silicone seal, damage the vacuum layer and, in the worst case, deform the inner wall. Only single-wall bottles without a vacuum layer should go in the freezer. Leave headspace in them: USGS notes that ice is about 9 percent less dense than liquid water, so frozen water needs more room.
Why can’t a vacuum-insulated bottle go in the freezer?
Because the freezer works against the part that makes the bottle insulated. A vacuum bottle has two walls with most of the air removed from the sealed gap between them, so very little heat or cold crosses that gap.
That is useful when the drink is already cold. It is a problem when you want the freezer to chill it. The cold air has to get through the outer wall, across the vacuum and into the inner wall, and the vacuum slows that down. Our guide to how insulated water bottles work explains the gap in more detail.
In the freezer, a vacuum bottle cools the drink poorly and risks damage. The drink cools slowly while the bottle sits through a large temperature difference between the outside and the inside. BG Drinkware warns of three risks in that situation.
- The seal hardens. The silicone seal in the lid can harden in the cold.
- The vacuum layer can be damaged. A damaged vacuum layer cuts the bottle’s insulation, and the user cannot repair it.
- The inner wall can deform. In the worst case, the stress of the temperature difference bends the inner wall out of shape.
Why leave headspace when freezing a single-wall bottle?
Because water takes up more space once it turns to ice.
The USGS Water Science School notes that water’s density drops by about 9 percent when it freezes, which is why ice floats. The same mass of water takes up more space once frozen.
This applies to any container you freeze water in. For a single-wall bottle, leave space at the top and keep the lid off or loose until the water is frozen.
Is the fridge any safer for an insulated bottle?
BG Drinkware advises against the fridge too. The freezer is the worst place for a vacuum bottle, but the fridge has the same basic problem.
The vacuum gap stops the fridge from cooling the drink in any useful time, so there is little to gain, and BG Drinkware advises against it. The practical rule is simple: chill the drink, not the bottle.
Which bottles can go in the freezer?
Only bottles without a vacuum layer. Material matters less than construction: a double-wall titanium bottle has the same limit as a double-wall steel one.
| Bottle construction | Freezer | Fridge | Note |
|---|---|---|---|
| Double-wall vacuum, stainless steel | No | No | Risk to seal, vacuum and inner wall. |
| Double-wall vacuum, titanium | No | No | Same vacuum construction, same limit. |
| Single-wall stainless steel | Yes | Yes | Leave headspace; keep the lid off or loose while freezing. |
| Single-wall titanium | Yes | Yes | Leave headspace for the ice. |
| Single-wall plastic | Yes | Yes | No vacuum layer, so BG Drinkware’s rule allows it. Leave headspace and check the plastic’s low-temperature range with the supplier. |
If you are not sure which construction a bottle has, check the product listing or the care label, or ask the supplier. If the construction is unclear, treat the bottle as vacuum insulated.
How do you get an ice-cold drink from an insulated bottle?
Let the bottle do what it was built for: keep an already-cold drink cold.
- Chill the drink separatelyCool the water or juice in a jug or a single-wall container in the fridge.
- Pour it inFill the insulated bottle with the pre-chilled drink, leaving room for the lid.
- Close the lidThe vacuum wall now works for you, keeping the cold in instead of keeping it out.
The same thinking applies to cleaning and heating. An insulated bottle has its own care rules for the dishwasher and microwave; see our guide to dishwasher-safe water bottles for the cleaning side.
What should a brand tell its customers?
Say it on the bottle or in the box. BG Drinkware tells its customers in advance not to put vacuum bottles in the freezer or fridge, so the brand can pass the rule on.
BG Drinkware can add a care mark or a care note to an order, in the same way it adds a no-microwave mark. Example wording:
Put the care note where the user will see it before the first use: a printed insert, the gift box or the base of the bottle. Confirm the exact mark, wording and position with the factory when you place the order.
For travelling with a bottle, frozen or not, see metal water bottles on a plane.
Planning a branded run?
If you are sourcing bottles for a brand, write the care instructions you want on the packaging into the order, including the freezer warning for vacuum bottles. Our custom water bottles page lists models and capacities. The standard minimum order is 500 pieces, negotiable.
Freezer and insulated bottle FAQ
Can you put an insulated tumbler in the freezer?
If it is vacuum insulated, no. A tumbler with a vacuum wall has the same construction as an insulated bottle, so the same risks apply: the drink cools poorly, the seal can harden, and the vacuum layer or inner wall can be damaged. Chill the drink in a separate container first, then pour it into the tumbler.
Will freezing break a vacuum-insulated bottle?
It can. BG Drinkware warns that the temperature difference may harden the silicone seal, damage the vacuum layer and, in the worst case, deform the inner wall. BG Drinkware tells its customers in advance not to put vacuum bottles in the freezer, and the same applies to double-wall titanium bottles.
Why doesn’t my insulated bottle get cold in the freezer?
Because the vacuum gap between the two walls blocks the cold, just as it blocks heat. The freezer has to cool the outer wall and then push that cold across a near-empty gap, which takes a long time. The bottle is built to keep a cold drink cold, not to be chilled from outside.
Can I put a single-wall stainless steel bottle in the freezer?
Yes. A single-wall bottle has no vacuum layer, so BG Drinkware’s freezer rule does not apply. Leave room at the top because water expands as it freezes, and keep the lid off or loose until the water is frozen. The same applies to single-wall titanium bottles.
Can I chill an insulated bottle in the fridge first?
BG Drinkware advises against it. The fridge is less harsh than the freezer, but the vacuum gap still stops it from cooling the drink in any useful time, so you gain little. Chill the drink in a jug or a single-wall container instead, then pour it into the insulated bottle.
Sources
Need care marks on your insulated bottles?
Tell us the bottle style and your market. BG Drinkware can add a no-freezer, no-fridge or no-microwave mark, or a printed care note, to your order.
