AMIT Cost Base Adjustment Calculator
Turn the adjustment on your annual AMMA statement into an updated managed-fund unit cost base.
Awaiting input
Enter the opening cost base and adjustment from your AMMA statement.
What this estimate includes
- Applies adjustments in statement order.
- Separately totals cost-base increases and decreases.
- Flags the portion of a decrease that exceeds the remaining cost base.
Frequently asked questions
What is an AMIT cost-base net amount?
An AMMA statement can show an AMIT cost-base net amount excess or shortfall that adjusts the cost base of your managed-fund units.
Does an AMIT excess increase or decrease cost base?
An AMIT cost-base net amount excess generally decreases cost base; a shortfall generally increases it.
What if an AMIT decrease is larger than the cost base?
The cost base cannot fall below zero. The excess reduction can trigger an immediate capital gain.
Tax Accuracy & Sources
Reviewed: 28 July 2026 · Tax year: Current AMIT cost-base rules
One adjustment at a time for Australian resident investors. It does not parse AMMA statements, allocate an adjustment across parcels, calculate sale CGT or reproduce every attribution and tax-offset label.
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