Northern Territory Consolidated Acts16. How wills may be altered
(1) An alteration made to a will after the will is executed is not effective unless the alteration -
(a) is executed in a manner in which a will is required to be executed by this Act;
(b) is made by a minor pursuant to an order of the Court made under section 18(1) and is otherwise in accordance with section 18;
(c) is made for and on behalf of a person without testamentary capacity pursuant to an order of the Court made under section 19(1) and is otherwise in accordance with Division 2 of Part 3; or
(d) is a document that under section 10 the Court is satisfied embodies testamentary intentions of a deceased person and so constitutes an alteration to the will of the deceased person; or
(e) obliterates words in the will so that their effect is no longer apparent.
(2) In altering a will, it is sufficient compliance with the requirements for execution if the signatures of the testator and of the witnesses to the alteration are made -
(a) in the margin or on some other part of the will beside, near or otherwise in relation to the alteration; or
(b) as authentication of a memorandum referring to the alteration and written on the will.
(3) This section does not apply to an alteration to a will if the words or effect of the will are no longer apparent because of the alteration.