A funding opportunity number (FON) is a unique number used on Grants.gov to identify funding opportunities for businesses, educational establishments, nonprofits and other entities that want to apply for a government grant. The number is assigned by the funding agency (the agency that is supplying the capital) when the opportunity is created in the system. If you are applying for one of the government grants online, you must include the FON as part of your application.
Navigate to the Grants.gob (see Resources).
Click on "Find Grant Opportunities" on the left-hand side.
Search for the grant opportunity you are interested in. You can search by category or funding agency, or if you know the name of the grant, you can enter it after clicking on "Basic Search."
Click on the name of the grant under Opportunity Title in the search listings. The funding opportunity number will be listed as the second item down.