You can change a joint income allocation if it is wrong.
If the allocation is wrong
If you think the amount you’ve been allocated from a joint account is wrong, you can change this allocation when we complete your income tax assessment at the end of the year or when you file your income tax return. You may be asked for documentation to support an unequal allocation of interest between account holders.
Any other owners of the joint account will need to make their own changes separately.
Missing IRD number
Income from joint investments is split equally among account holders who have provided valid IRD numbers. This also applies to partnerships (excluding limited partnerships). If income is allocated incorrectly because an IRD number is missing, affected account holders should contact the payer to update their IRD number to ensure future allocations are correct.
Change the allocation amount
Make changes to your joint allocation in your income tax assessment or when you file your income tax return.