What kills termites the fastest?

What kills termites the fastest is a professional liquid termiticide barrier treatment using non-repellent chemicals like fipronil or imidacloprid for subterranean termites, and fumigation or direct wood injection for drywood termites, because these methods deliver lethal doses quickly to large numbers of termites. For subterranean termites which cause most damage in the US and live in underground colonies with millions of members, liquid termiticides work fastest by creating a treated zone in soil around the foundation, so when termites forage through it they contact the chemical and carry it back to the colony on their bodies, spreading it through grooming and feeding, causing death within days and colony decline within 30 to 90 days, with reduction in activity often visible within a week. Non-repellent termiticides are faster than repellent types because termites do not avoid them. For drywood termites that live inside wood, whole-structure fumigation with sulfuryl fluoride gas tented over the house kills all termites including eggs within 24 to 72 hours but requires vacating for 2 to 3 days and costs $1,000 to $3,000. Direct spot treatment with foam or liquid fipronil injected into infested wood kills on contact within hours but may miss hidden galleries. Over-the-counter orange oil and boric acid kill slowly and only where applied. Heat treatment raising wood temperatures above 120 degrees Fahrenheit can kill quickly but requires professional equipment. For fastest results, hire a licensed pest control company that can trench, drill, and apply commercial-grade products with proper coverage and offer warranties.