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Sharon's husband died in 2022 . Everything was titled JTWROS so they did not file an estate tax return. When he died his tentative tax base was $1,496,479. What is the DSUEA deceased spouse unused exemption amount available for Sharon? Sharon's husband died in 2022 . Everything was titled JTWROS so they did not file an estate tax return. When he died his tentative tax base was $1,496,479. What is the DSUEA deceased spouse unused exemption amount available for Sharon