This nameplate was introduced for the 2010 model year as a lower-slung, darker take on Harley-Davidson’s classic Softail Fat Boy formula. It kept the signature wide, heavy custom stance of the Fat Boy while emphasizing an especially low seat and relaxed riding position, which helped make it a standout for shorter riders and for those drawn to the slammed chopper-inspired look. The model was sold under the Softail family designation and used the FLSTFB model code.
Through its run, the Fat Boy Lo was positioned as a variation on one of Harley-Davidson’s most recognizable cruisers rather than as a separate platform. Its appeal came from combining the familiar Fat Boy silhouette with more dropped suspension, blacked-out trim on later versions, and the brand’s traditional emphasis on long, low visual proportion over outright performance. In Harley-Davidson’s own documentation, the Fat Boy Lo remained part of the Softail lineup through the 2017 model year.
For 2018, Harley-Davidson’s Softail lineup was reorganized and the Fat Boy Lo nameplate no longer appeared, with the standard Fat Boy returning under updated model codes instead. That makes the Fat Boy Lo a single continuous production run from 2010 through 2017, remembered as the lower, more laid-back branch of the Fat Boy family.