Activatable thermal indicators with thermally expansive materials are disclosed herein. An example is provided by an activatable indicator including a plurality of microcapsules, each of the plurality of microcapsules further including a frangible shell, a volatile material contained in the frangible shell, configured to transition to a gas when heated above a predetermined activation temperature, wherein responsive to a first activation action including an application of heat configured heat above the predetermined activation temperature, the volatile material causes the frangible shell to weaken or rupture, and a payload contained in the frangible shell, the payload containing a liquefiable material configured to liquefy responsive to a predetermined environmental exposure, the payload configured to be released from the frangible shell when the frangible shell is ruptured.