Wash. Rev. Code § 11.104B.500
(1) This section applies when:
(3) A fiduciary shall determine the income and net income of an estate or income interest in a trust which terminates, other than the amount of net income determined under subsection (2) of this section, under Articles 4, 5, and 7 of this chapter and by:
(b) Paying from income or principal, in the fiduciary's discretion, fees of attorneys, accountants, and fiduciaries, court costs and other expenses of administration, and interest on estate and inheritance taxes and other taxes imposed because of the decedent's death, but the fiduciary may pay the expenses from income of property passing to a trust for which the fiduciary claims a federal estate tax marital or charitable deduction only to the extent:
(c) Paying from principal other disbursements made or incurred in connection with the settlement of the estate or the winding up of an income interest that terminates, including:
[ 2021 c 140 s 2601.]