Adding Someone to Your Mortgage in Australia — How It Works (2026)
Adding someone to your mortgage — whether a partner, spouse, or family member — requires lender approval and involves a formal reassessment of the loan. Here is what the process involves and what to consider.
Why You Might Add Someone to Your Mortgage
Common reasons include:
- New partner or marriage: Your partner moves in and you want them on the title and loan
- Improving serviceability: A second income can increase your borrowing capacity or help meet repayments
- Guarantor situation change: The original guarantor is being released; adding a co-borrower instead
- Investment partnership: Adding a business partner or family member to a jointly owned investment property loan
Adding Someone to the Mortgage vs Adding to the Title
These are two separate (but usually simultaneous) actions:
| Adding to the loan | Adding to the title | |
|---|---|---|
| What it means | The new person becomes jointly liable for the debt | The new person becomes a legal owner |
| Processed by | The lender (mortgage) | The state land registry |
| Approval required | Yes — lender must agree | Transfer of equity — may attract stamp duty |
| Can you do one without the other? | Technically yes, but unusual | Technically yes, but unusual |
In practice: When adding someone to a mortgage in Australia, you typically add them to both the loan and the title simultaneously.
The Process
Step 1: Lender application
Contact your lender (or mortgage broker) and request to add a co-borrower. The lender will require a new credit assessment including:
- The new borrower’s income, employment, and expenses
- Their credit history and credit score
- The new borrower’s existing debts and liabilities (including credit card limits)
The existing loan terms remain in place — but the new co-borrower is assessed as if it were a new application.
Step 2: Lender assessment and approval
The lender assesses the combined serviceability of all borrowers against the existing loan (plus any other debts). If approved, the lender issues a variation to the existing loan agreement.
If adding someone reduces serviceability (e.g., the new person has high debts), the lender may decline the addition — even though you were already approved.
Step 3: Transfer of title (if applicable)
If adding the person to the property title, a conveyancer or solicitor prepares a transfer document. The transfer is lodged with the state or territory land registry.
Stamp duty: Adding a person to property title may attract stamp duty in some states (as a transfer of equity). This varies significantly by state and the relationship between the parties.
- NSW: Transfer of equity between spouses or de facto partners (in a genuine domestic relationship) is generally exempt from stamp duty. Other situations may attract duty.
- Victoria: Similar exemptions for spouse/domestic partner transfers.
- Other states/territories: Rules vary — check with a conveyancer.
Step 4: Updated mortgage documentation
The lender issues updated loan documents reflecting the new co-borrower. All borrowers sign.
Costs
| Cost item | Typical range |
|---|---|
| Lender application/variation fee | $0–$500 (varies by lender) |
| Legal/conveyancing fee | $500–$1,500 |
| Stamp duty (state-dependent) | $0 (if exempt) to 4–5% of transferred equity value |
| Title registration fee | $100–$400 (state-dependent) |
| Mortgage broker fee | Usually nil |
Implications of Adding a Co-Borrower
Both borrowers are jointly and severally liable. This means each person is individually responsible for the full loan — not just their share. If one person stops paying, the other is fully responsible.
Both borrowers appear on the credit file. Any repayment issues will be recorded against both credit files.
Both borrowers’ incomes are assessed for future lending. The new co-borrower’s debts will also be considered in any future refinancing.
Alternatives to Adding a Full Co-Borrower
| Alternative | Description |
|---|---|
| Guarantor arrangement | A guarantor provides security without being on the loan itself (different to co-borrower) |
| Adding as a guarantor | Some lenders allow limited guarantor structures |
| Refinancing together | Both apply for an entirely new loan as co-borrowers — may get better rate at same time |
Frequently Asked Questions
Do I need to refinance to add someone?
Not necessarily — many lenders allow a variation to add a co-borrower without a full refinance. However, some lenders require a new application. A mortgage broker can advise on your lender’s specific process.
Does adding someone change my interest rate?
Adding a co-borrower is typically processed as a loan variation — your existing rate and terms remain unless you are also refinancing.
Can I add someone without adding them to the title?
Technically yes — you can be jointly liable for a loan without being on the title. However, this is unusual and most lenders would want the borrower on the title (as the title is the security for the loan).
Related Guides
- Removing Someone From a Mortgage — Transfer of Equity
- Joint Tenants vs Tenants in Common
- Co-ownership Agreements — Protecting Yourself
- Property Ownership Structures Hub
This article provides general information about adding someone to a mortgage in Australia. Stamp duty exemptions vary by state and relationship — speak with a licensed conveyancer or solicitor. For mortgage advice, find a licensed broker through MoneySmart.