If you are required to file Form 3520 this year (Annual Return to Report Transactions With Foreign Trusts and Receipt of Certain Foreign Gifts), you can do that manually, by downloading the tax form itself and the instructions at the following links:
Form 3520 is a disclosure document, really, and there is never any actual tax due with it.
However, if you meet the conditions of having to file Form 3250 (receipt of more than $100,000 in value from a foreign source), then failure to file it can lead to a fine of up to 5% per month (maximum of 25%) of the amount received. You can request relief from the penalty by a letter attached to it with your explanation of why you did not file and report the information on time. The IRS will consider the facts and circumstances then render their decision. It's hopeful they can rule in your favor, but it's not absolute. See "Reasonable Cause" in the instructions.
Due Date: In general, the due date for a U.S. person (defined later)
to file a Form 3520 has changed to the 15th day of the 4th
month following the end of the U.S. person’s tax year. This means it was due on April 15th, 2017, because the money was received in 2016.
Form 3520 does not come as part of the TurboTax software package; but for that matter neither does it come with the consumer software offerings of any of our worthy competitors. But, fortunately, the form is easy enough to fill out by hand. You can still use TurboTax to complete your personal income tax return. The two things are separate activities that need not interfere with each other.
