Dividing the Tax Attributes

Carryforwards are assets. They do not appear on any balance sheet, they are not listed on the schedule of property, and a couple that spent six weeks arguing over furniture will routinely let six figures of them evaporate. Inventory them from the last joint return and allocate each one in the decree:

Capital loss carryforwards

Allocated to the spouse who generated the underlying loss — jointly held positions split evenly, individually held positions follow the owner. At $3,000 a year against ordinary income the carryforward looks trivial; against future realized gains it is not. A $600,000 carryforward is worth roughly $220,000 to a California top-bracket filer who will realize gains against it (20% federal plus 3.8% NIIT plus 13.3% state), and it belongs to whoever the decree says it belongs to.

Suspended passive activity losses

Losses trapped under IRC §469, “Passive activity losses and credits limited” on a rental or a non-participating business interest attach to the activity, so they follow the property to whichever spouse receives it and free up on its eventual disposition. Price the property with the suspended loss attached; two rentals with identical equity are not identical assets.

Charitable contribution carryforwards and net operating losses

Both allocated on the basis of who generated them, both wasted entirely if nobody claims them within the carryforward window.

Joint estimated tax payments

Payments made jointly for the year of divorce are not automatically split. Absent agreement the IRS allocates them in proportion to each spouse’s separate tax liability — which is rarely what either party intends. Specify the allocation in the decree and attach the computation to the returns.

The final joint refund, and any exposure behind it

Decide who receives a pending refund and who funds a later assessment on a prior joint return. A decree can allocate the burden between you, but it does not bind the IRS, so the spouse taking the risk should secure it — and should understand the IRC §6015 relief tracks in section “The Marriage Penalty and the Marriage Bonus” before assuming a decree is protection.

Prior-year AGI and the estimated-tax safe harbor

Your safe harbor for the following year is computed from the prior year’s return, which was a joint one. Recompute each spouse’s standalone safe harbor for the first single-filing year or you will underpay into penalties during the exact year your withholding is already wrong (section “Quarterly Estimated Taxes”).

Two more items are property rather than attributes and get missed for the same reason. A 529 account is controlled entirely by its owner, not by the beneficiary or by whichever parent funded it, so an account titled to one spouse can be redirected to a different child — or liquidated — after the divorce. Name the intended successor owner, or hold it under a court-ordered custodial arrangement, and specify who funds it going forward (section “529 Plans”). And where a founder holds qualified small business stock (QSBS), note that the exclusion cap is measured per taxpayer per issuer and that stock transferred to a spouse under IRC §1041 keeps its qualification and holding period — which occasionally makes splitting the shares worth more after tax than trading them away (section “Qualified Small Business Stock”).