Fandon is an unincorporated community in Chalmers Township, McDonough County, Illinois, United States.

Fandon does not have its own post office and is part of Colchester's ZIP code.

[3] When citizens of McDonough County organized the Forgottonia secession movement in the 1970s, Fandon was named its capital.

[4] In 2011, The History Channel series How the States Got Their Shapes focused part of its second episode to the historic inequality given to the Illinois region known as Forgottonia which was a region that considered seceding from the rest of Illinois and establishing its capital at Fandon.

[5] Fandon is part of the West Prairie Community Unit School District 103.