As I understand it, a contribution would be income tax free when sent directly from an IRA to a 501(c)(3) organization. It is not clear to me if the distributions still will affect my MAGI that in turn will affect Medicare Part B IRMAA premiums.
If your IRA distribution satisfies the conditions for a qualified charitable distribution (“QCD”), the distribution will not be taxable to you. That, by itself, won’t lower your modified adjusted gross income (“MAGI”). However, if the QCD is used to satisfy the required minimum distribution (“RMD”) from your IRA, that will reduce your MAGI.