This review explores the use of circulating tumor DNA (ctDNA) in liquid biopsies for the evaluation and management of epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). Liquid biopsies, which detect ctDNA in blood, offer several advantages over tissue biopsies, including faster turnaround times and reduced invasiveness. For early-stage disease, ctDNA can help guide adjuvant therapy decisions, while in advanced stages, it aids in identifying genetic changes that may affect treatment response. Tracking ctDNA levels can also monitor treatment progress and detect resistance early. While tissue biopsies remain the standard, liquid biopsies are becoming a recommended alternative. Ongoing research aims to improve test sensitivity for early detection, refine treatment approaches based on ctDNA results, and explore other bodily fluids for enhanced detection. Making liquid biopsies more accessible and integrated into routine care could significantly improve lung cancer management.This review explores the use of circulating tumor DNA (ctDNA) in liquid biopsies for the evaluation and management of epidermal growth factor receptor (EGFR)-mutant non-small cell lung cancer (NSCLC). Liquid biopsies, which detect ctDNA in blood, offer several advantages over tissue biopsies, including faster turnaround times and reduced invasiveness. For early-stage disease, ctDNA can help guide adjuvant therapy decisions, while in advanced stages, it aids in identifying genetic changes that may affect treatment response. Tracking ctDNA levels can also monitor treatment progress and detect resistance early. While tissue biopsies remain the standard, liquid biopsies are becoming a recommended alternative. Ongoing research aims to improve test sensitivity for early detection, refine treatment approaches based on ctDNA results, and explore other bodily fluids for enhanced detection. Making liquid biopsies more accessible and integrated into routine care could significantly improve lung cancer management.