Nowhere if not alimony. Alimony is the only deductible spousal payment. Anything that you can deduct would be taxable income to her - somebody must pay the tax - but anything that you give her outside of alimony is not taxable to her. Most pension divisions in divorce are done with a QDRO where the pension plan pays the ex spouse directly and issues a 1099-R to the ex spouse who is then responsible for paying the tax - you would never see the money.