Although due at the same time as the individual's income tax return, Form 3520 is filed separately and can't be filed electronically. Since this form is filed separately from your income tax return (and doesn’t result in any tax owed or refund due), it isn’t a supported form within Intuit TurboTax. Many taxpayers will be able to tackle this form on their own if they have gifts and bequests (inheritances).
Here's more info on Form 3520.
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