Donation letters are generally unsolicited letters, so it important to keep the tone courteous and friendly.
It is imperative to clarify at the outset what it is that you wish to ask for. A Donation Request letter should be specific about what you are asking for, it could be money or unused items or even time for some cause.
Donation letters are best addressed to one particular person rather than an organization. They must be similarly signed off by a name rather than a designation or organization. It makes the letter appear more personal and the reader knows that it is from a person rather than a faceless entity.
It is also good to establish credentials of the organization you are working for and state the reason for your writing.
It is helpful to state how your organization is best suited to take on the cause that you are championing. This assures the reader that he/she would be supporting a credible and honest organization.
Since Donation Letters are an imposition on another’s time one must always close with a thanking note, an expression of gratitude to the reader for their time taken to read your letter in the first place.
If you are writing a Donation Thank You letter, then it would be a good idea not only to just thank the person for the donation but also to mention how the donation you have received has benefitted a particular cause.