The Humboldt Museum would not exist without the generous support and contributions of a long list of benefactors. Significant patrons are listed on four brass plaques, located in the North wing of the upstairs floor. Additionally, a partial list of corporate benefactors includes:

• Getchell Gold, which partially funded the elevator/hoist, in honor of the hundreds of miners, past and present, who have developed the gold mines of Humboldt County
• The Wiegand Foundation, which among other support, funded the creation of the Library's Wiegand Audio/Vision room
• Booth Ferris Foundation contributed a large mural downstairs depicting Bridge Street, looking North-East, taken about 1900
• Commission for Cultural Affairs, which is sponsoring renovation of the Cumley-Richardson House