Although the policy of abolishing fares in public transport—here referred to as “fare-free public transport” (FFPT)—exists in nearly 100 localities worldwide, it has not been thoroughly researched. To start filling this gap, I enhance the conceptual clarity about fare abolition. I start by providing a definition of FFPT, discussing its different forms, and introducing a distinction between “partial” FFPT and—the main focus of the paper—“full” FFPT. Next, I distinguish three perspectives on full FFPT—first, approaches that assess fare abolition primarily against its economic impact; second, analyses that look at its contribution to “sustainable” development; third, more critical arguments highlighting its politically transformative and socially just potential. Against the background of this debate I offer the most comprehensive inventory of full FFPT programmes to date, and begin to chart and examine their global geography. As a result, FFPT emerges as a policy that takes diverse forms and exists in diverse locations. Supported and contested by diverse rationales, it cannot be analysed as transport instrument alone.