Understanding Co-Tenant Responsibilities When Renting in Australia

Sign a lease with other people in Australia and you are not just responsible for your share of the rent. You are responsible for all of it. That is the reality of joint and several liability, the legal rule that applies to every co-tenancy in the country. It means that if one flatmate stops paying, the landlord can chase the rest of you for the full amount. The same goes for the bond and any damage to the property. With median rent for a one-bedroom apartment in Sydney, Melbourne, Brisbane, and Perth making solo living unaffordable for many, share houses are a practical response — but the legal side is often misunderstood.

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This article is general information only and does not constitute professional advice. For your specific situation, consult a qualified professional.

Co-tenancy arrangements vary by state and territory, but the core principle is the same everywhere: once your name is on the lease, you share the full financial weight of the agreement. How that plays out when someone moves out, misses a payment, or wants to bring in a new person depends on the rules where you live and what you put in writing before you moved in. Here is what you actually need to know.

What I tend to notice is that most people who move into a share house with friends do not talk about the exit before they talk about the entry. That is where the trouble starts. The difference between a co-tenant and a sub-tenant matters a lot when things go wrong, and the research shows that the single most effective step you can take is to get the agreement in writing at the start.

The Full Cost Picture of Co-Tenancy in Australia

Rent and bond are the obvious costs, but they are not the only ones. Co-tenants typically split utilities, council rates, strata fees, internet, and contents insurance as agreed between them. The problem is that joint and several liability applies to the tenancy agreement itself, not to the side deals you make with each other. If the person who pays the internet bill stops, the landlord does not care — but the unpaid bill can still affect your credit rating and future rental eligibility.

The table below shows the three main legal statuses you can have when sharing a property in Australia. Each one comes with a different level of protection and a different set of responsibilities.

→ Scroll right to see all columns

Beyond the rent itself, the practical cost of co-tenancy often shows up in the bond. A single bond is lodged for the property with the relevant authority — the RTA in Queensland or QBCC in other states — and co-tenants decide how to split the contribution. When one person leaves, the remaining tenants must repay their share of the bond within 14 days, minus any unpaid rent, utilities, or reasonable costs. If there is a dispute, the bond repayment can be held up until the tribunal sorts it out.

Common Misunderstandings That Cost Co-Tenants Money

Assuming you are only responsible for your share

This is the most common and most expensive mistake. Joint and several liability means the landlord can demand the full rent from any co-tenant. If you are the only one with a steady income when a flatmate stops paying, you can be forced to cover the gap. In practice, that can mean paying double rent for months while you try to recover the money from the other person. Getting a written agreement at the start about how unpaid rent is handled — and having a property law resource to consult if things go wrong — can save you a lot of stress.

Not documenting the split of costs and responsibilities

Consumer Protection WA advises that before signing a lease, co-tenants should document in writing how rent is paid, how bills are paid, who contributed to the bond and how much, responsibilities for cleaning and maintenance, ownership of shared belongings, and use of common areas. Most people skip this step because it feels awkward with friends. When a dispute arises later, there is no record of what was agreed. The cost of not documenting is often a trip to the tribunal, which costs time and money and can damage relationships.

Subletting without everyone’s consent

Subletting a room requires consent from all co-tenants and the landlord. Doing it without permission is a breach of the tenancy agreement. The head tenant who sublets without consent can be held responsible for the sub-tenant’s behaviour, damage, and unpaid rent. If the sub-tenant stops paying, the head tenant still owes the full rent to the landlord. The RLAQ makes clear that subletting requires all co-tenant consent, and breaches can have serious consequences.

Leaving without proper notice

In the ACT, you must ask the lessor and each co-tenant in writing at least 21 days before you want to leave. If they do not respond or apply to the tribunal within 21 days, they are taken to have agreed. During a fixed-term lease, the lessor and remaining tenants can refuse consent for any reason. During a periodic lease, they cannot reasonably refuse. If you leave without agreement or a tribunal order, your responsibilities under the lease continue until the lease ends. That means you can still be chased for rent after you have moved out.

How to Handle a Co-Tenancy from Start to Finish

Before you sign: the written agreement

Get everything in writing before you commit. This includes how rent and bills are split, who contributed what to the bond, cleaning and maintenance duties, ownership of shared items, and rules for common areas. Make sure all co-tenants contributing to the bond have their names on the bond form. The bond details can be changed later, but only with all tenants’ signatures. A written agreement is not a legal document in the same way as the lease, but it gives the tribunal something to work with if a dispute arises.

Living together: handling changes during the lease

If someone wants to move out during the fixed term, the remaining tenants and the landlord must agree. The departing co-tenant is responsible for their share of costs until the lease is changed or a replacement is found. If you want to add a new co-tenant, you must ask the other existing tenants and the lessor in writing at least 14 days before the new tenant moves in. If no response is received within 14 days, consent is taken as given. An existing tenant can refuse consent for any reason, but the lessor must not unreasonably refuse and must provide written reasons if they do.

Ending the tenancy together

All co-tenants must agree to end the tenancy. A joint notice is given to the landlord, and the bond is refunded to the nominated account. If there are disputes about the bond split, the tribunal can intervene. The process is straightforward if everyone agrees, but it becomes complicated quickly if one person wants to stay and another wants to leave. In that case, the person who wants to leave must follow the formal exit process or remain liable for the rent.

Leaving a co-tenancy: the step-by-step process

• 1
  Give written notice

  Write to the lessor and each co-tenant at least 21 days before you want to leave. State your intention clearly and include the date you plan to move out.

• 2
  Wait for response

  The lessor and remaining tenants have 21 days to respond or apply to the tribunal. If they do nothing, they are taken to have agreed to your departure.

• 3
  Apply to the tribunal if needed

  If the lessor or remaining tenants refuse consent, you can apply to the tribunal (ACAT in the ACT, QCAT in Queensland, or the relevant body in your state) for an order to leave.

• 4
  Settle the bond

  Once you leave, the remaining tenants must repay your bond contribution within 14 days. They can deduct unpaid rent, utilities, or other reasonable costs. If there is a dispute, the tribunal can decide.

• 5
  Confirm your liability ends

  Your liability under the lease continues until the lease ends or your name is formally removed from the agreement. Get written confirmation from the landlord that your name has been removed.

If you are dealing with a departing co-tenant who owes money, you can request their bond contribution in writing. The 14-day repayment window applies, and if they do not pay, you can take the matter to the tribunal. For more on how to handle lease obligations, see this guide to tenant lease obligations in Australia.

Frequently Asked Questions About Co-Tenancy in Australia

What the Future of Co-Tenancy Looks Like

The rules around co-tenancy are not static. Several states and territories are reviewing their tenancy laws, with a focus on strengthening protections for tenants in shared housing. The ACT already has a detailed process for leaving and joining a co-tenancy that other jurisdictions may follow. If you are in a share house now, the best time to get your agreement in writing is before the next person moves in or out. The legal structure is only going to get more detailed, not less.

Remember: this article is general information only. For advice on your specific situation, speak to a qualified professional.

If this was useful, you might also want to read Smart Ways to Negotiate Rent in Australia.

Sources and Further Reading

Understanding Tenant Lease Obligations When Renting in Australia — A detailed breakdown of what tenants must do to stay compliant with their lease and avoid disputes.

Lease Co-Signer Responsibilities for Australian Renters — How co-signer liability differs from co-tenant liability and what it means for the person who signs alongside you.

RLAQ (n.d.). Co-tenants. 🔗

Consumer Protection Western Australia (n.d.). Your Rights and Responsibilities: Shared Tenancy. 🔗

RenterSay (n.d.). Share House Australia Guide. 🔗

ACT Civil and Administrative Tribunal (n.d.). Co-tenancies. 🔗