"In Kind" services should definitely be invoiced as a value so they can be listed as a charitable contribution on year-end tax returns. This would help reduce tax liability (not an accountant, but I have done this with non-profit work on my accountants advice).
Hmmm...I question whether your accountant is giving you good advice. The IRS states in many of their information documents that an individual can not "deduct the value of your time or services" when working with charitable organizations. Here`s just one reference on the IRS web site. (in this case the reference is in the first bulleted item on the list). My accountant has always made this very clear to me as I do a great deal of work with nonprofits. I can deduct any expenses incurred, and travel costs, but not the value of my time.
It is always good to invoice nonprofits the full value of the work you have done so they have an understanding of the true value of your services - but any deductions on that balance due or donations will be out of the goodness of your heart.
Here`s an article I wrote about the value of working with nonprofit organizations.
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