The Short Answer:
It depends. A good general rule is the bigger the award amount, the longer the application will take.
The Long Answer:
It depends on the type of grant, the type of funder, and level of your organization’s involvement in the application process.
In order to be successful, grant applicants must invest significant time (at least 25% for each grant written) in project planning, budget development, establishing management and tracking systems for the expenditure of funds, and reporting the impact of the project to stakeholders. Without this level of participation, your grant will have >50% chance of success. Collaboration is essential.
The following time estimates are based on the assumption that you’re working with an experienced grants consultant—someone who can help you develop your project and goals, conduct any necessary research, and write and submit the proposal (75% of the work that goes into a grant application).
Small Applications
Letter of Inquiry: 6-8 hours
Small or Local Foundation Grant Proposal (under $50K): 8-12 hours
Medium Applications
Medium Foundation Grant Proposal ($50-$100K): 15-25 hours
Medium State or Federal Grant Proposals ($100K-$300K): 40-80 hours
Large Applications
Large Foundation Grant Proposal ($100K+): 40-80 hours
Large State or Federal Grant Proposals ($300K+): 80-120 hours