the information provided is a little confusing. So, let's see if I understand correctly. He owned 100% of the residence and deeded it to a living trust. He died.
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Thus 100% of the value of the house is stepped up to Fair Market Value. At death, the trust would become irrevocable. So when the trust sold the house it had a gain/loss of the sales price less selling expenses less the FMV. There is no home sale exclusion for an irrevocable trust. Now, if there is a gain because the house has appreciated more between the date of sale and death, the trustee must decide whether to pay the tax on the gain at the trust level or pass it out to the spouse on a k-1. For the trust, you need Turbotax Business - windows only computer - 64-bit operating system windows 10 or later.
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I'm assuming she was not a co-owner because you use this phrase "transferred the deed to his home to the trust". if she was a co-owner of the house when transferred to the trust the answer could change.
