There is a lot of confusion in this question. “ Nonprofit” does not equate to charitable. There are a lot of nonprofit organizations that are not 501(c)(3) charities, and some are not even tax-exempt. (See Ready Reference Page: “What Do We Mean When We Say Nonprofit”)
If you intend to apply for 501(c)(3) charity recognition ultimately, you probably want to be sure that your articles of incorporation include the language required to qualify for the status. (See Ready Reference Page: “Articles of Incorporation Establish Basic Form of Nonprofit Corporations”) If you don’t have the language in the original articles, you will still be a nonprofit, but will have to amend the articles before you can qualify for charitable status.
If you plan to use a fiscal sponsor as a “conduit” organization, the sponsor will undoubtedly want you to qualify for charitable status even if you haven’t been recognized.