Just Married: The First-Year Tax Checklist

The tax code cares about exactly one date on your marriage timeline: December 31. Married on that day — even December 31 itself — and you’re treated as married for the entire year. Here’s what that changes and what to do about it.

The status decision

Your options become married filing jointly or married filing separately — single is off the table, regardless of when in the year you wed. Jointly usually wins: better brackets, full credit access, higher phase-out thresholds. But “usually” isn’t “always”:

Income-driven student loan plans calculate payments from joint income when you file jointly. For a couple with one large loan balance and one large income, filing separately can cut loan payments by more than the tax cost — a genuine annual calculation.

Large medical expenses for one spouse clear the AGI threshold more easily against one income.

Liability separation matters when one spouse has tax debt, back child support, or a business under examination — though “injured spouse” relief can protect a refund within a joint filing.

Run it both ways the first year. Good software or a CPA does this in minutes.

The penalty and the bonus

Couples with similar incomes can pay slightly more married than they did single (the residual “marriage penalty,” mostly at high incomes and in certain state brackets — and note New Jersey’s brackets aren’t simply doubled). Couples with very different incomes usually get a marriage bonus — the lower earner’s brackets shelter the higher earner’s income. Knowing which couple you are sets expectations for everything else.

The immediate to-do list

Item 1 — SSA first, then everything else. If anyone changes names, update the Social Security Administration before filing — a return whose name doesn’t match SSA records gets rejected.

Item 2 — Both W-4s, together. Two incomes withheld as if each were the household’s only income is the top cause of newlywed April surprises. The IRS estimator with both jobs entered, once, fixes it.

Item 3 — Benefits coordination at the next open enrollment: whose health plan, one household’s FSA/HSA strategy (family HSA limits, dependent care caps are per household), and life/disability updates.

Item 4 — Beneficiaries. Retirement accounts and life insurance pass by designation — update them or your will’s intentions lose.

Item 5 — Roth IRA eligibility check: joint phase-outs differ from single ones; a spouse who contributed early in the year may now be over the limit (fixable by recharacterization if caught before filing). And note the spousal IRA — a non-working spouse can fund an IRA from household income.

Item 6 — Home and state paperwork if the marriage came with a move: domicile, withholding state, and — for NJ/NY couples — whose work state does what to the joint return.

One year of intentional setup, and married filing becomes the easy autopilot it’s supposed to be.

Romanchuk CPA LLC is a fully virtual CPA firm serving individuals and business owners nationwide since 2014, with NJ/NY depth. Book a consultation at rfg.tax.

This article is general information, not tax advice for your specific situation. Figures adjust annually — verify current amounts.