Updated August 6, 2026. Quick answer: most people assume domestic partnerships and civil unions were abolished when same-sex marriage was recognised. They were not. Several states still register new ones, some to any couple regardless of sex, and in several the status carries the same inheritance rights as marriage. For a couple who does not want to marry, registering can be the cheapest fix available — and in one state it is worth the entire inheritance tax.
Why this is worth checking before anything else
Everything else in this wing is a document you write. This is a status you can hold, and where it exists it does in one registration what several documents do separately: it can put your partner in the intestate line, on the medical decision list, and out of the stranger bracket for state inheritance tax.
The clearest example is New Jersey. A registered domestic partner or civil union partner is treated as Class A for inheritance tax — the spouse’s class, fully exempt — while an unregistered partner falls to the unrelated class. The tax detail is on its own page. That is a large, purely administrative saving.
What none of these statuses do is make you married for federal purposes. The IRS states that registered domestic partners “may not file a federal return using a married filing separately or jointly filing status” because “these taxpayers are not married for federal tax purposes.” So there is still no Social Security survivor benefit and no federal estate-tax marital deduction. Registration is a state-law fix to state-law problems.
States that still register new partnerships
Verified from each state’s own statute or agency, on the date below. Rules change; confirm before relying on any row.
- Illinois — civil union, open to any couple. The clearest option in the country: open to same-sex and opposite-sex couples alike regardless of whether they could marry, at 18, and partners are folded into “spouse” and “next of kin” throughout Illinois law (750 ILCS 75/10, 75/20, 75/25).
- Colorado — civil union, open to all adults. C.R.S. §14-15-107 gives full parity including intestate succession, folding partners into “spouse”, “heir” and “next of kin”. County clerks confirm licences are actively issued in 2026.
- California — domestic partnership, open. Family Code §297.5 gives registered partners the same rights, protections and benefits as spouses, and gives a surviving partner the rights “as are granted to and imposed upon a widow or a widower.”
- Nevada — domestic partnership, open. NRS §122A.200 uses the same widow-or-widower formulation, so a surviving partner inherits as a spouse would.
- New Jersey — two statuses, different doors. Civil unions remain open to same-sex couples, with the same intestate treatment as spouses (N.J.S.A. 37:1-32(a)). Domestic partnerships remain open, but since February 2007 only where both partners are 62 or older; earlier registrations are grandfathered.
- Washington — domestic partnership, but only if one of you is 62. RCW 26.60.030(2) makes that a hard eligibility gate. Partnerships where neither partner was 62 were automatically converted to marriage on June 30, 2014; the older ones were deliberately left alone. Washington is also the one state whose community-property statute names registered partners in its own text — what that does to basis at the first death.
- District of Columbia — domestic partnership, open to anyone. D.C. Code §32-702 imposes no residency requirement, which makes DC unusual. We could not confirm from the code text whether the status carries intestate rights, so we do not claim it does.
- Maine — a registry, and a statute that warns you about it. 22 M.R.S. §2710 is worth reading precisely because it undersells itself: registration “is not a substitute for a will” and any inheritance right “may be completely superseded”. Maine’s registry is not spousal-equivalent, and the state says so.
- Oregon — the statute is still on the books. ORS chapter 106 grants registered partners privileges and rights equivalent to spouses. We could not confirm whether new applications are currently being accepted, so treat this row as “check with the county”.
Closed: Connecticut stopped issuing civil unions on October 1, 2010 and converted existing ones to marriage. Wisconsin closed its declaration registry on April 1, 2018. Existing statuses in both states were not erased.
Registering has consequences too
These statuses are not free upside, and two points are worth stating before anyone registers on the strength of a tax table.
They generally have to be dissolved. Where a status carries spousal rights it usually also carries a court process to end it, much like a divorce. An unregistered couple can simply part.
They can create the same exposures marriage does. If the status makes you a spouse for state purposes, it can pull you into the same calculations — including, potentially, long-term care means-testing. The factors are the same ones on the marry-or-not page, and they deserve the same look before registering as before marrying.
And if you registered years ago and later married the same person, or moved away, it is worth confirming what still exists. An unresolved old status is a live legal fact, not a historical one.
Sources
750 ILCS 75/10, 75/20 and 75/25 at the Illinois General Assembly; Cal. Fam. Code §§297, 297.1 and 297.5 at California Legislative Information; NRS ch. 122A at the Nevada Legislature; N.J.S.A. 37:1-28 et seq. at the New Jersey Legislature and the New Jersey Department of Health for the domestic-partnership age rule; RCW 26.60.030 and 26.60.100 at the Washington State Legislature; D.C. Code §32-702 at the D.C. Council and DC Health; 22 M.R.S. §2710 at the Maine Legislature; ORS ch. 106 at the Oregon Legislature; Wis. Stat. §770.01 at the Wisconsin Legislature; the Connecticut Department of Public Health, citing C.G.S. §46b-38rr; and the IRS FAQ for registered domestic partners. All read 2026-08-06.
Sourcing note: the Colorado statute text was read from the Public.Law mirror because the state site did not serve it; active issuance was confirmed separately from two county clerk sites.
Honest gaps, stated rather than filled. This roster is not complete, and the missing rows are missing because we could not read a source we trust, not because we found nothing. Vermont, Delaware and Rhode Island are absent — their official sites failed on every attempt, and second-hand accounts say all three closed to new registrations, which we are not willing to state as fact. Hawaii is absent from the list above for the same reason: its civil union and reciprocal beneficiary chapters appear to be in force, but the state legislature and health department sites refused us on every attempt across two passes, and we will not describe a statute we have not read. Maryland is the interesting one: its inheritance-tax statute expressly refers to a registered domestic partnership, which is solid evidence the status exists and carries a full tax exemption — but we could not read the registration rules themselves, so we describe the tax effect and not the mechanics. If you are in any of these five states, this page is a prompt to call the county clerk, not an answer.
See methodology and corrections. General information about published statutes, not legal advice. No affiliate links, nothing sold.