Formos, a celestial body, was situated in the Outer Rim Territories. It was positioned along the hyperspace routes known as both the Pabol Sleheyron and the Triellus Trade Route. During the Imperial Era, under the rule of the Galactic Empire, Formos functioned as a processing center for spice being transported from the planet of Kessel. Following the fall of the Empire, intense conflict arose between rival spice trading factions, heavily impacting Formos.
Found within the Outer Rim Territories and the Slice regions, Formos's galactic coordinates placed it in grid square T-10 of the Standard Galactic Grid. The Pabol Sleheyron hyperspace route provided a link between Formos and Prishella. Conversely, the Triellus Trade Route connected Formos to the celestial bodies Eadu and Kubindi.

While the Galactic Empire was in power, during the reign, Formos operated as a processing hub for spice shipments originating from the planet Kessel. The Mining Guild of the Empire offered protection to Formos during this period.
After the Empire's decline in 5 ABY, Formos became a vulnerable target for competing spice trade groups, leading to significant battles. Operations on Formos were deemed too dangerous, which ultimately contributed to the rise of the Spice Runners of Kijimi pirate organization.
Between 10 BBY and approximately 1 ABY, Midnight, a Corellian bartender, mentioned Formos in their book. Midnight's book stated that smuggler starships typically journeyed from Formos to Kessel. Furthermore, Midnight noted that pilots awaiting employment for the Kessel Run spent their free moments gambling at sabacc and causing disturbances.

The current Star Wars canon introduced Formos through a mention in issue number twenty-nine of the De Agostini magazine Star Wars: Build the Millennium Falcon, released around July 22, 2015. Originally, Formos was established as a planet within the Star Wars Legends continuity. Its initial appearance was in "Way of the Wookiee!," a comic story penned by Archie Goodwin, with artwork by Carmine Infantino and Pablo Marcos. This story was featured in issue ninety-four of Marvel Comics' Star Wars Weekly comic series on December 12, 1979.
Star Wars: Build the Millennium Falcon 29 uses a map from the 2009 Star Wars Legends reference book titled The Essential Atlas. This map portrays Formos as the final point on the Kessel Run hyperspace route. However, the 2018 canon book, Solo: A Star Wars Story: Tales from Vandor by Jason Fry, states that the Kessel Run actually terminated at Oba Diah. This article operates under the assumption that this information is accurate.
Moreover, Tales from Vandor positions Oba Diah on the route that Build the Millennium Falcon 29 and Fantasy Flight Games' 2016 Star Wars: The Force Awakens Beginner Game identify as the Pabol Sleheyron. Conversely, a map created for the reference book Star Wars: Timelines and distributed as a promotional poster at Celebration Anaheim on May 27, 2022, before the book's release during Celebration Europe from April 7 to 10, 2023, depicts Oba Diah as Formos's neighboring location on the Triellus Trade Route. This article assumes the latter placement to be incorrect.