How to Fill Out and File a Colorado Domestic Partnership Affidavit

A Colorado domestic partnership affidavit is a sworn statement two partners sign, before a notary, to declare their committed relationship, usually to register with a city clerk in Boulder or Denver or to qualify a partner for employer benefits like health insurance. Colorado has no statewide domestic partnership statute, so the form you use, the eligibility rules, and where you file all depend on who is going to accept the affidavit. The steps are the same in shape: get the right form, gather proof of your shared life, sign in front of a notary, and submit it.

Which Form You Need

There is no single statewide affidavit. The correct form comes from whoever will accept it.

If you want a government record of the partnership, use a municipal registry. Boulder’s City Clerk takes registrations through an online application, and both partners must attend an in-person appointment together.¹ Denver’s Clerk and Recorder accepts registrations at the Webb Municipal Building, 201 W. Colfax Ave., Dept. 101.

If the affidavit is for employer benefits, use your employer’s form. Colorado State University, the University of Colorado, and many private employers each publish their own version with requirements built around their benefits plans.²³ A Boulder registration certificate will not automatically satisfy an employer, and an employer affidavit will not register you with a city. Confirm with the specific office or HR department before you start.

Who Qualifies

Wording varies between municipal and employer forms, but the core eligibility rules are consistent. Both partners must:

Be at least 18 years old and mentally competent to enter a contract.¹
Be each other’s sole domestic partner, with neither currently married to someone else.
Live together and share a home. Colorado State University’s form requires at least 12 consecutive months of cohabitation before you can file.²
Not be related by blood any closer than would prevent a marriage in Colorado.¹
Be in a relationship of mutual support, caring, and commitment, and intend to remain so.

Boulder does not require partners to live inside city limits; anyone can register there.¹ Employer forms sometimes add requirements, such as proof of joint financial responsibility, so read your specific form before assuming you qualify.

Documents to Have Ready

Assemble everything before you fill in the form or book an appointment. You will need:

Government-issued photo ID for each partner, such as a driver’s license, passport, or military ID.¹
Proof of a shared address. A lease, joint mortgage, joint bank account statement, joint vehicle title, or a recent utility or phone bill sent to each partner at the same address will typically work.
Proof of joint financial responsibility if your employer requires it. CSU asks for at least one document, dated within the past 60 days, showing both names at the same address: a joint deed, bank account, credit account, or insurance policy.²

Missing or stale documents are the most common cause of delays. If your IDs show different addresses, bring a lease or utility bill that places both of you at the current one.

Filling It Out

The form itself is short. You enter each partner’s full legal name, date of birth, and current address, then both partners sign a series of sworn declarations covering the eligibility items above. Read every declaration before you sign. You are swearing under penalty of perjury, so an inaccuracy such as an unfinished prior divorce creates real legal exposure.

Employer forms often add sections. The University of Colorado uses a single form for both establishing and terminating a partnership, with a separate section for each.³ CSU requires you to attach a copy of your joint financial document to the completed affidavit.² A form submitted without the required attachment will come back to you.

Getting It Notarized

An affidavit is a sworn statement, and under the Colorado Revised Uniform Law on Notarial Acts the notary must verify each signer’s identity and witness both signatures.⁴ Do not sign the affidavit in advance. Most notaries will reject a pre-signed document and ask you to start over.

Colorado caps in-person notary fees at $15 per document. Remote online notarization through audio-video communication is permitted, with a cap of $25.⁵ Remote notarization requires an electronic record and a system meeting the Secretary of State’s security rules, including identity verification and a single real-time session where the notary watches you sign.⁶ Banks, UPS stores, and shipping centers routinely offer notary services if you do not have one closer at hand.

Where to Submit It

Once notarized, where the affidavit goes depends on why you prepared it.

Municipal Registry

For Boulder, submit the application online and attend an in-person appointment with your partner. The fee is $25, paid by credit card when you submit.¹ After processing you receive a certificate confirming the registration. Denver’s Clerk and Recorder handles its own registrations at the Webb Municipal Building; call 720-865-8400 for current fees and scheduling.

A municipal registration gives you a formal record you can present to insurers, hospitals, and other institutions. Keep certified copies on hand for the times a third party asks for proof.

Employer HR

For employer benefits, submit the completed and notarized affidavit, with any required attachments, to human resources. Processing times run from a few business days to a couple of weeks. Ask HR whether the affidavit alone enrolls your partner or whether you also need to complete a separate benefits enrollment during an open enrollment window.

What the Affidavit Does Not Do

Before you file, understand the limits of what you are signing. A domestic partnership affidavit is not a marriage, not a civil union, and not a federal legal status.

A civil union under the Colorado Civil Union Act grants partners the same rights and responsibilities as married spouses under Colorado law, including property rights, inheritance protections, and hospital visitation, and ending one requires a court dissolution.⁷⁸ A domestic partnership affidavit creates none of those state-level obligations or protections. It extends only as far as the registry or employer accepting it.

Colorado also still recognizes common-law marriage, established by a mutual agreement to be married followed by conduct reflecting that agreement, such as joint finances and presenting yourselves publicly as spouses.⁹ Courts look at intent and conduct, not labels. Two people who sign a domestic partnership affidavit and then live as a married couple can be found to have a common-law marriage, which carries the full legal weight of a ceremonial marriage and requires a formal dissolution to end.

Federal agencies generally do not recognize domestic partnerships. Social Security survivor and spousal benefits are tied to marriage, though the agency notes that some valid non-marital legal relationships may qualify in limited circumstances.¹⁰ Federal COBRA continuation coverage defines eligible dependents as a spouse, former spouse, or children, with no mention of domestic partners.¹¹ Immigration sponsorship is similarly limited. If survivor benefits, immigration status, or COBRA continuation matter to you, the affidavit will not get you there.

One more surprise is tax. When an employer provides health insurance to your domestic partner, the IRS treats the employer’s share of your partner’s premium as taxable income to you. This imputed income is added to your gross pay and subject to federal income tax, Social Security, and Medicare, so your paycheck is smaller than a married coworker’s with the same family coverage. The exception is narrow: if your partner qualifies as your tax dependent under Internal Revenue Code §152, the coverage is excluded from your income. Qualifying requires that your partner live with you the entire tax year, receive more than half of their support from you, be a U.S. citizen or resident, and not be a qualifying child of another taxpayer. A partner with a full-time job almost certainly does not meet the support test. After enrollment, review your pay stubs to confirm the imputed income amount and plan for the higher tax bill.

Ending the Partnership

Ending a domestic partnership is simpler than ending a marriage or civil union because no court is involved. For Boulder’s registry, you complete a termination form declaring the partnership has ended, and many jurisdictions allow one partner to file without the other’s signature.¹² For an employer-based partnership, notify HR in writing. The University of Colorado requires notification within 31 days of the partnership ending.³ Other employers set their own deadlines, so check your benefits handbook.

After termination, your former partner loses any benefits tied to the affidavit, including health, dental, and life insurance. There is no property division, no support obligation, and no waiting period. Federal COBRA does not extend to domestic partners, so your former partner cannot continue employer-sponsored coverage at their own expense the way a divorced spouse could. If your partner depends on your insurance, line up alternative coverage before you file the termination.

1
City of Boulder. Domestic Partnerships
2
Colorado State University. Affidavit of Domestic Partnership
3
University of Colorado. Affidavit of Domestic Partnership
4
Colorado Secretary of State. Colorado Code 24-21-501 – Revised Uniform Law on Notarial Acts
5
Colorado Secretary of State. General Questions – Notary Public FAQs
6
Justia. Colorado Code 24-21-514.5 – Remote Notarization
7
Justia. Colorado Code 14-15 – Colorado Civil Union Act
8
Colorado Judicial Branch. End a Civil Union
9
Justia. Colorado Code 14-2-104
10
Social Security Administration. Who Can Get Survivor Benefits
11
U.S. Department of Labor. COBRA Continuation Coverage
12
City of Boulder. Termination of Domestic Partnership