Helium balloons usually shrink overnight because cold temperatures cause the helium gas inside the balloon to contract. In most cases, the balloon is not leaking and will return to its normal size after warming up indoors.
“My helium balloons looked perfect yesterday. Why are they suddenly smaller today?”
The good news is that this is usually normal.
Temperature changes affect helium more than many people realise. In most cases, your balloons are not damaged and have not lost all of their helium.
In this guide, we’ll explain why helium balloons shrink overnight, whether they will expand again, and how to make them last longer.
Helium balloons shrink overnight because helium gas contracts in cold temperatures.
When the temperature rises again, the helium expands and the balloon usually returns to its original size.
This does not necessarily mean the balloon is leaking.
Temperature changes affect the pressure inside the balloon.
Yes.
Most helium balloons return to their normal size once they warm up.
However, if helium has leaked from the balloon, it may not fully recover.
Not always.
If balloons become smaller only during cold weather and recover indoors, they are probably not leaking.
Signs of an actual leak include:
✔ Keep balloons indoors.
✔ Avoid overnight cold temperatures.
✔ Inflate balloons close to the event.
✔ Use quality balloons.
✔ Keep away from direct sunlight.
