ETF AMMA statements and your cost base

The figure to look for

The AMMA statement shows an AMIT cost base net amount. It broadly reflects the difference between what the fund attributed to you for tax and what it actually paid you. If the payments were larger, your cost base goes down. If the attributed amounts were larger, it goes up.

The adjustment is made just before year end or just before a relevant CGT event, such as a sale. FiscalFox records the amount attributable to disposed units separately from units retained at year end, per original purchase. Do not divide an annual total by units held on 30 June if purchases or sales changed the distribution entitlements.

Sources: ATO: Cost base adjustments for AMIT members

Capital gains the fund passes on

When a fund sells its own investments at a gain, it passes the gain on to you, and it goes in your capital gains at item 18 even if you sold nothing. The AMMA statement splits it into gains worked out with the discount method, shown grossed up to before the discount, and gains worked out by the indexation or other method.

Add the grossed-up amount to your total capital gains. Your capital losses can reduce these gains, and the 50% discount then applies again to what is left of the discount-method part.

When a decrease becomes a gain

If the decreases add up to more than a parcel's cost base, the cost base stops at zero and the excess is a capital gain in that year, under CGT event E10. It qualifies for the 50% discount if you have held the units for at least 12 months.

Every year counts

Selling AMIT units needs the relevant AMMA amounts for every year you held them, including the amount attributable to disposed units in the sale year. Missing years mean a wrong cost base. Most fund managers keep past statements on their website or in their investor portal.

Keep distributions separate from sale proceeds

A cash distribution, attributed taxable income and a cost base adjustment are different figures. Enter the fund’s tax components from its statement, and keep the sale itself in your trade history. Reinvested distributions can create both taxable income and a new unit parcel.

When reviewing myTax pre-fill, reconcile each fund once. The capital gains component feeds the overall item 18 calculation; adding the same amount again as a separate personal sale would overstate it.

Sources: ATO: Attributing amounts to AMIT members · ATO: Individual supplementary tax return 2026 (PDF)

Worked example: an AMIT cost base decrease

Synthetic example for 100 units held throughout the statement period, all sold after the adjustment. There are no other costs, gains or losses.