Should I use a Heat Pack?
A common misconception about heat packs is that they are necessary for shipping reptiles. More often than not, they are not necessary at all. In fact, they can be quite dangerous when misused. The misuse of heat packs is the #1 killer of reptiles during the shipping process.
So how do you know when to use one? This decision depends on the type of animal you are shipping and the daytime high temperature at your origin and at the destination.
Please read this article for a comprehensive guide to whether or not a heat pack is needed. Note that all the temperatures listed in this guide are the high temperatures for the shipping days in question. It may seem counter-intuitive to ignore the low temperatures, but this standard has worked flawlessly throughout decades of experience shipping thousands of animals.
What should you do if the origin and destination temperatures are hot at one end and cold at the other? Call your reptile shipping provider and ask for their advice. If you're shipping through them, following their instructions in this scenario will ensure your Live Arrival Insurance remains viable. They may ask you to delay the shipment if the temperature span is too extreme, which can be critical for the safety of the animal(s) you're shipping.
Check out these complete instructions for using heat packs.