Final answer:
Union dues have traditionally been deductible for employees who itemize, but spousal support payments' deductibility has changed with divorces finalized after December 31, 2018, in the United States. To determine current deductibility, one needs to consult the latest tax forms and regulations.
Step-by-step explanation:
The question of whether union dues and spousal support payments can be deducted in the calculation of taxable income is dependent on current tax laws and regulations which can vary over time and by jurisdiction. Traditionally, union dues have often been considered deductible expenses for employees who itemize their deductions. However, spousal support, also known as alimony, underwent changes in its tax treatment with the Tax Cuts and Jobs Act of 2017 in the United States. For divorces finalized after December 31, 2018, the payer cannot deduct spousal support payments, and the recipient does not include them as income.
However, for divorces finalized before that date, the payer can deduct spousal support payments, and the recipient must include them as income. It's critical to consult the most recent version of tax forms such as Form 1040 or Form 1040-SR for specific instructions regarding the deductibility of these expenses as tax laws may have changed since the knowledge cutoff.