We'll cover everything you need to know about sponsorship letters: what they are, how to write them, who to send sponsor letters to. These letters request sponsorship either from an individual or a corporation for a specific event, initiative or for longterm support of the nonprofit.Learn to craft an effective sponsorship request letter with our stepbystep guide and template. Boost your chances of securing sponsorship! I am writing this letter to invite you to be a Co-Sponsor or Supporter of this event! Sponsorship: San Bernardino County is not able to consider candidates who will require visa sponsorship at the time of application or in the future. Looking to secure sponsorships for your organization? Download these sponsorship letter templates to help you write a successful sponsorship letter! Fill out the whole application form, if you can. Create a compelling letter with our free sponsorship solicitation letter template.