It depends. We may need additional clarification about the type of loss and when it actually occurred. Next is whether you are trying to amend a tax return and for what tax year.
If you had a 2024 investment loss then it would be reported on your 2024 tax return. If the loss actually occurred in 2025, then it would go on the 2025 tax return.
Once we have additional details we can provide the information you need.
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