Best Way to Add Someone to an Existing Lease

If someone wants to move in with you and your lease is in your name only, it may violate guest limits or occupancy rules, leading to fees, eviction notices, or non-renewal of your lease. It also creates real problems if the relationship changes or damage occurs. To stay safe, get written approval from your landlord, have them screen the new person, and sign a lease addendum or new lease before moving in, ensuring that rent, deposits, and move-out rules are clear.

Confirm Your Lease Allows Another Adult Occupant

Start by reviewing your lease and finding the language that controls extra occupants in the unit. If you have a PDF, search for guest, occupant, resident, sublet, or assignment. Look for sections labeled guest policy, occupants, additional residents, subletting, or assignment.

Pay special attention to these clauses:

• Time limits for guests: "no more than 7 nights in a row"
• Approval requirements: "any adult occupant must apply and be approved"
• Penalties: fees, default, or termination for unauthorized occupants

Next, make sure you're asking for the right kind of permission. If the person will live there most nights and keep their stuff there, don't ask for a guest exception. Ask to add an adult occupant, either as a co-tenant or as an authorized occupant.

Approval can still be blocked by rules outside your lease:

• Occupancy limits: tied to bedroom count or health and safety rules
• Building rules: condo or co-op, including move-in scheduling
• Parking limits: tied to the unit or property rules

Pro Tip: If your lease doesn't reference adult occupants, treat that as an unresolved risk and ask for written clarification before anyone moves in.

Decide Whether You Want Them as Co-Tenants

Before you contact your landlord, decide what you want the new person to be on paper. Don't leave this part to your property manager, because it changes your risk.

The two typical options are:

• Co-tenant: signs the lease and shares responsibility for rent and lease rules. If rent goes unpaid, the landlord can pursue any co-tenant for the full amount in many states.
• Authorized occupant: is approved to live there but does not sign the lease. You stay responsible for rent and damage under your lease, even if your roommate promised to pay you.

For example, if your partner moves in and becomes a co-tenant, they can be held responsible for unpaid rent. If they are only an authorized occupant, your landlord will look to you first because you are the signer.

Before you pick, answer these questions:

• Do you want them to have equal rights throughout the lease?
• Are you willing to cover the whole rent if they lose income?
• Would you need the landlord's help to remove them?

Co-tenant status creates more accountability for them, but the downside is more exposure for you if they break rules, rack up charges, or trigger lease violations.

Authorized occupant status can make sense when:

• They are moving in for a shorter period, like finishing school
• You want them approved for building rules, but you don't want shared lease liability
• Their credit or income is borderline, and you don't want a denial to derail your housing
• You want a cleaner exit plan if the living arrangement fails

Pro Tip: If you wouldn't trust them to cover rent for a month, don't ask them to be a co-tenant.

Request Approval in Writing

A clean, written request is the difference between a smooth approval and weeks of back-and-forth. Send an email or portal message unless your lease requires a letter. Keep it short, complete, and easy to approve.

Put your ask at the top of your message:

• "Do you approve adding [Full Name] as a co-tenant?"
• "Do you approve [Full Name] as an authorized occupant?"

Include these details in the same message:

• New person's full legal name and phone number
• Current address and email
• Planned move-in date and whether they will keep another residence
• The status you are requesting (co-tenant or authorized occupant)
• A short reason for the change, like "roommate moving in to share costs"
• Whether you are requesting any rent, term, parking, or pet changes
• Confirmation that they will complete an application and screening
• A request for your landlord's timeline, including fees
• A request for which document they will use, an addendum or a new lease

Use this template:

I'm requesting approval for [Full Legal Name] to move into Unit [#] on [date] as a [co-tenant / authorized occupant]. They will complete any required application and screening. Please confirm the application link, screening fee amount, and your decision timeline. If approved, will you use a lease addendum or a new lease, and what is the earliest move-in date you will authorize in writing?

Have the following extra documentation ready:

• A screenshot of the lease clause that requires approval
• Vehicle details if parking is assigned
• Pet details, if any animal will live there, must be disclosed
• Any building move-in form your property requires

Keep the request narrow on purpose. If you ask to add a person, renegotiate rent, and change the lease end date, you've turned one decision into several.

Pro Tip: Keep your request clear and concise, so the landlord can only decide yes or no. Missing details may lead to lease reopening, policy involvement, or approval delays.

Expect Screening and Plan for Denial

Plan for screening like you're applying for a new apartment, because your landlord is managing risk the same way. Inform the new person what they will need before they start, and let them know when you need it back.

Common requirements include:

• A completed rental application
• A copy of a government ID
• Proof of income, like pay stubs, an offer letter, or benefit statements
• Consent for credit and background checks
• Rental history and landlord references
• A pet profile, if they are bringing an animal

Ask your landlord what standards will be applied, such as an income multiple or a minimum credit score. You're not asking them to bend rules. You're deciding whether you're about to pay an application fee for a predictable number.

Consider these common issues before applying:

• If they have a credit freeze, have them lift it first.
• If they are a contractor, ask what your landlord accepts as proof of income.
• If they have limited credit, ask whether your landlord will still approve them as an authorized occupant.

Before anyone brings boxes inside, it's important to have a denial plan in place. First, determine where the individual will stay if their application is denied. Additionally, check your lease to see if it permits them to visit as a guest and for how long. Avoid moving them in while the application is still pending, as this may constitute a lease violation.

Pro Tip: Ask your landlord what fails screening instantly before anyone applies, so you don't pay fees or trigger a denial you could have predicted.

Use an Addendum or Sign a New Lease

You want paperwork that matches the changes. Your landlord will usually use either a lease addendum or a new lease, and the choice affects rent, deposit amounts, and timing.

A lease addendum is the cleanest option when the base deal stays the same. It is a short document that adds the new person and states what changes, if any.

An addendum should include:

• The added person's legal name and status as a co-tenant or authorized occupant
• The effective date is when they are allowed to move in
• Whether rent, parking, or utilities change
• Whether the security deposit changes
• A statement that the original lease remains in effect except for the listed changes

A new lease common when your landlord wants to reset terms:

• Your landlord will only add a co-tenant by rewriting the lease
• Rent is changing, and your landlord wants clean documentation
• Your landlord is extending the term or changing the end date
• Multiple rules are changing at once, like the pet policy or the smoking policy

Before you sign, confirm whether the lease end date stays the same. A new lease can reset the term and lock you in longer than you planned. Also, confirm whether any fees are being added for processing, keys, parking, or building registration.

Make sure everyone signs the same set of papers. That includes all current leaseholders, the new co-tenant if applicable, and your landlord or property manager. Ask for a fully executed copy and save it as a PDF.

Pro Tip: Treat a new lease as a complete renegotiation and an addendum as a minor adjustment, as it can alter your rent, term, and exit rights.

Confirm Rent, Deposit, and Move-Out Terms

Once your landlord says yes, the next risk is unclear money handling. Most roommate blowups start with "I thought you were paying the landlord" or "I thought the deposit would come back to me."

Ask your landlord which payment methods they allow:

• One combined payment from one account
• Split payments in the portal
• Separate payments, with clear rules for late fees and partial payments

If the new person becomes a co-tenant, ask your landlord to confirm in writing how liability works under your lease. Many leases make co-tenants jointly responsible. That can mean your landlord can demand the full rent from you if your roommate does not pay.

Discuss the security deposit before money changes hands:

• Will your landlord increase the deposit because another adult is added?
• Will the deposit receipt list everyone's name, or only one person?
• At move-out, will the refund check be made out to everyone?

Utilities and access are where minor conflicts grow. Confirm who will hold each utility account, how keys and fobs will be issued, and the cost of replacements. If the building has assigned parking, get the new assignment in writing.

Finally, discuss about move-out rules with the new person before move-in day. If one person leaves early, the lease may still bind everyone until the end date unless your landlord agrees otherwise.

Pro Tip: Assume the landlord will enforce the lease strictly, so clarify who pays, owes, and gets refunded before any money is exchanged.

Conclusion

Adding someone mid-lease is about protecting your housing, not just seeking permission. Follow this order: check your lease, choose a co-tenant intentionally, request written approval, complete the screening, and sign the addendum or new lease before they move in. This sequence helps avoid lease violations and reduces the risk of incurring extra costs during a messy move-out.

Review your lease and note the sections on guests, occupants, subletting, and assignments. Draft a request message with the new person's full name and move-in date, and ask what document your landlord will use for approval. If your landlord won't provide a clear process or timeline, consider it a denial for now and don't let the new occupant move in until you have a signed agreement.