How long will helium balloons float?
The longest floating balloons are made from foil or plastic. They will remain full and float for 7 to 14 days on average. Latex rubber balloons will float for varying times. The larger the balloon, the longer its floating time. A liquid sealant, Hi-Float, can be used to extend the float time by coating and sealing the inner surface of any latex balloon larger than 9″. We automatically treat all of our helium filled latex.
Without knowing the size of the balloons you are refering to and type of balloon it is difficult to answer your question.
Float times for balloons can be found on the Qualatex website. This chart includes most sizes.
http://www.qualatex.com/downloads/HeliumChart_2009.pdf
