Yes, you can marry someone with the same last name. No state in the United States treats surname as a factor in who is allowed to marry. County clerks issue marriage licenses based on age, legal capacity, and whether the two applicants are related within prohibited degrees of kinship. What appears on your driver’s licenses is not part of that analysis, and two unrelated people who happen to share a common surname face no extra step, no waiting period, and no proof-of-non-relation requirement.
Why the Surname Itself Is Irrelevant
Marriage eligibility turns on three questions: are both applicants old enough, do both have the legal capacity to consent, and are they too closely related. Surname is not on that list. A clerk cannot refuse a license because both applicants are named Johnson, Garcia, or Nguyen, and no state asks couples with matching last names to document that they come from different families.
Every marriage license application does ask whether the two applicants are related within prohibited degrees. That question is asked of everyone. You answer it the same way whether your surnames match or not, and if you truthfully affirm that you are not closely related, the shared name plays no role in the rest of the process.
What the Law Actually Restricts
The real legal barriers are about blood relationships (consanguinity) and, in some states, relationships created by a prior marriage (affinity). Every state prohibits marriage between parents and children, grandparents and grandchildren, and siblings, including half-siblings. Those rules are universal and have nothing to do with names.
States diverge past that point. Marriage between first cousins is fully legal in roughly 17 states, including California, Colorado, New York, and Virginia. Several other states permit first-cousin marriage only under specific conditions, such as both parties being above a certain age or completing genetic counseling. The rest prohibit it. Marriages between aunts or uncles and nieces or nephews are prohibited in most jurisdictions, with a few narrow exceptions for half-blood relationships.
If you happen to share a surname with someone who is also a relative, the legality depends entirely on the degree of kinship and your state’s rules. The shared last name itself changes nothing.
Name Choices After the Wedding
Neither spouse is required to change their name after marriage. When you already share a surname, keeping what you have is usually the simplest choice, and there is no paperwork to file.
You still have every option any other couple has. Either spouse can take the other’s name (which in this case would change nothing), hyphenate, or pick a new surname altogether. Some couples with the same last name choose a brand-new shared name to distinguish their household from their birth families. If either spouse does change names, the update starts with the Social Security Administration, then the state motor vehicle office, then the State Department for a passport.1USAGov. How to Change Your Name and What Government Agencies to Notify
Credit Reports Can Get Mixed
Sharing a surname with your spouse creates one genuine, tangible risk worth flagging. Credit bureaus match financial records to people using name, Social Security number, date of birth, and address. When two people at the same address share a last name, automated matching sometimes merges their records into a single “mixed file.” Similar first names or authorized-user arrangements make it worse.
A mixed file is not cosmetic. It can produce loan denials tied to your spouse’s debt, false delinquencies on your report, and incorrect debt-to-income ratios that block a mortgage. If you suspect your credit report contains your spouse’s accounts, dispute the errors directly with the credit bureau. Providing your full legal name including middle name, date of birth, and Social Security number helps the bureau separate the files.2Equifax. What Can I Do if I Believe My Credit File Has Been Mixed with Someone Else’s
To reduce the odds of mixing, use your full middle name on financial applications, keep at least some individual credit accounts in each spouse’s name, and check your reports regularly. Catching a mixed file before you apply for a mortgage is much easier than untangling it under a closing deadline.
Wills, Beneficiary Forms, and Powers of Attorney
When spouses share a surname, estate documents need extra precision. A bequest “to my spouse, J. Martinez” is ambiguous if both spouses go by J. Martinez. Use full legal names including middle names, add dates of birth, and specify the relationship. “To my spouse, Julia Carmen Martinez, born April 12, 1989” leaves nothing to interpret.
The same principle applies to powers of attorney, healthcare directives, and beneficiary designations on retirement accounts and life insurance. Financial institutions sometimes auto-populate names from account records, so check that beneficiary forms distinguish clearly between you and your spouse. A few seconds of specificity during drafting can prevent months of probate disputes later.
Joint Accounts and Documentation
Opening joint bank accounts, signing a mortgage together, or co-owning investments works the same regardless of whether you share a surname. Where things get muddled is in statements and correspondence, which can blur together when both account holders have the same last name at the same address.
Make sure both names appear on all joint account documentation. If a bank statement only shows one name in the header, ask for an account verification letter on official letterhead confirming joint ownership. That kind of documentation matters when applying for loans, proving assets in legal proceedings, or supporting immigration petitions. As a practical check, verify that each spouse can log into online banking under their own credentials.
Immigration Petitions
For a couple where one spouse is petitioning for the other’s green card, sharing a pre-marital surname does not raise a fraud flag. USCIS actually treats sharing a last name as one indicator that a couple presents themselves as married.3USCIS. USCIS Policy Manual Volume 6, Part B, Chapter 6 – Spouses The petitioner must still submit documentation of any legal name changes as part of the marriage-based petition. If neither of you changed your name because you already shared one, be ready to explain that and provide supporting documents like birth certificates showing your separate families of origin.
USCIS evaluates whether a marriage is bona fide based on the full picture: joint tax returns, shared bank accounts, co-owned property, and similar evidence of a shared life. A shared surname before marriage is neither a benefit nor a liability in that analysis.
Travel and Identification
Traveling as a married couple with the same last name rarely causes problems, but one detail catches people out. The TSA’s Secure Flight program requires the name on your airline reservation to exactly match the name on your government ID and any trusted traveler application like TSA PreCheck.4Transportation Security Administration. Does the Name on My Airline Reservation Have to Match the Name on My Application When two travelers on the same booking share a last name, booking systems occasionally assign the wrong first name to a reservation or duplicate one traveler’s information. Check each ticket individually before you leave for the airport.
For international travel, carrying your marriage certificate is a sensible precaution if you are visiting a country where officials might wonder whether you are siblings. It is not a legal requirement, but it can smooth things along at a border.