Back to Skills
    ๐Ÿฆž

    aussie-mortgage-calc

    Australian mortgage calculator โ€” LVR

    By @tianshizhimao-sudo
    View on GitHub
    SKILL.md
    ---
    name: aussie-mortgage-calc
    description: Australian mortgage calculator โ€” LVR, stamp duty, LMI, repayments, and First Home Buyer concessions by state.
    homepage: https://oneyco.com.au
    ---
    
    # Australian Mortgage Calculator
    
    Comprehensive mortgage calculations for Australian property buyers. All amounts in AUD.
    
    ## Quick Calculations
    
    ### LVR (Loan to Value Ratio)
    ```
    LVR = (Loan Amount / Property Value) ร— 100
    
    Example:
    - Property: $800,000
    - Loan: $640,000
    - LVR: 80%
    ```
    
    ### Monthly Repayment (P&I)
    ```
    M = P ร— [r(1+r)^n] / [(1+r)^n โ€“ 1]
    
    Where:
    - P = Principal (loan amount)
    - r = Monthly interest rate (annual rate / 12)
    - n = Total months (loan term ร— 12)
    
    Example: $500,000 loan at 6.5% over 30 years
    - Monthly rate: 0.065/12 = 0.00542
    - Months: 360
    - Monthly repayment: $3,160
    ```
    
    ### Interest Only Repayment
    ```
    Monthly IO = Principal ร— (Annual Rate / 12)
    
    Example: $500,000 at 6.5%
    - Monthly IO: $2,708
    ```
    
    ---
    
    ## Stamp Duty by State (2024-25)
    
    ### NSW (New South Wales)
    | Property Value | Duty Rate |
    |----------------|-----------|
    | $0 โ€“ $16,000 | 1.25% |
    | $16,001 โ€“ $35,000 | $200 + 1.50% of excess |
    | $35,001 โ€“ $93,000 | $485 + 1.75% of excess |
    | $93,001 โ€“ $351,000 | $1,500 + 3.50% of excess |
    | $351,001 โ€“ $1,168,000 | $10,530 + 4.50% of excess |
    | Over $1,168,000 | $47,295 + 5.50% of excess |
    
    **First Home Buyer**: Full exemption up to $800,000; concession $800,001-$1,000,000
    
    ### VIC (Victoria)
    | Property Value | Duty Rate |
    |----------------|-----------|
    | $0 โ€“ $25,000 | 1.4% |
    | $25,001 โ€“ $130,000 | $350 + 2.4% of excess |
    | $130,001 โ€“ $960,000 | $2,870 + 6.0% of excess |
    | Over $960,000 | 5.5% flat |
    
    **First Home Buyer**: Full exemption up to $600,000; concession $600,001-$750,000
    
    ### QLD (Queensland)
    | Property Value | Duty Rate |
    |----------------|-----------|
    | $0 โ€“ $350,000 | 1.0% (min $0) |
    | $350,001 โ€“ $540,000 | $3,500 + 3.5% of excess |
    | $540,001 โ€“ $1,000,000 | $10,150 + 4.5% of excess |
    | Over $1,000,000 | $30,850 + 5.75% of excess |
    
    **First Home Buyer**: Full exemption up to $700,000 (for new homes); concession for established
    
    ### WA (Western Australia)
    | Property Value | Duty Rate |
    |----------------|-----------|
    | $0 โ€“ $120,000 | 1.9% |
    | $120,001 โ€“ $150,000 | $2,280 + 2.85% of excess |
    | $150,001 โ€“ $360,000 | $3,135 + 3.80% of excess |
    | $360,001 โ€“ $725,000 | $11,115 + 4.75% of excess |
    | Over $725,000 | $28,453 + 5.15% of excess |
    
    **First Home Buyer**: Full exemption up to $430,000; concession $430,001-$530,000
    
    ### SA (South Australia)
    | Property Value | Duty Rate |
    |----------------|-----------|
    | $0 โ€“ $12,000 | 1.0% |
    | $12,001 โ€“ $30,000 | $120 + 2.0% of excess |
    | $30,001 โ€“ $50,000 | $480 + 3.0% of excess |
    | $50,001 โ€“ $100,000 | $1,080 + 3.5% of excess |
    | $100,001 โ€“ $200,000 | $2,830 + 4.0% of excess |
    | $200,001 โ€“ $250,000 | $6,830 + 4.25% of excess |
    | $250,001 โ€“ $300,000 | $8,955 + 4.75% of excess |
    | $300,001 โ€“ $500,000 | $11,330 + 5.0% of excess |
    | Over $500,000 | $21,330 + 5.5% of excess |
    
    **First Home Buyer**: No stamp duty for properties up to $650,000 (eligible buyers)
    
    ### TAS (Tasmania)
    | Property Value | Duty Rate |
    |----------------|-----------|
    | $0 โ€“ $3,000 | $50 |
    | $3,001 โ€“ $25,000 | $50 + 1.75% of excess |
    | $25,001 โ€“ $75,000 | $435 + 2.25% of excess |
    | $75,001 โ€“ $200,000 | $1,560 + 3.50% of excess |
    | $200,001 โ€“ $375,000 | $5,935 + 4.00% of excess |
    | $375,001 โ€“ $725,000 | $12,935 + 4.25% of excess |
    | Over $725,000 | $27,810 + 4.50% of excess |
    
    **First Home Buyer**: 50% duty discount for properties up to $600,000
    
    ### NT (Northern Territory)
    | Property Value | Duty Rate |
    |----------------|-----------|
    | $0 โ€“ $525,000 | V = 0.06571441 ร— V^2 รท 1000 |
    | Over $525,000 | 5.45% flat minus $4,823.45 |
    
    **First Home Buyer**: Up to $18,601 discount for properties under $650,000
    
    ### ACT (Australian Capital Territory)
    | Property Value | Duty Rate |
    |----------------|-----------|
    | $0 โ€“ $260,000 | $0.60 per $100 or part |
    | $260,001 โ€“ $300,000 | $1,560 + $2.20 per $100 |
    | $300,001 โ€“ $500,000 | $2,440 + $3.40 per $100 |
    | $500,001 โ€“ $750,000 | $9,240 + $4.32 per $100 |
    | $750,001 โ€“ $1,000,000 | $20,040 + $5.90 per $100 |
    | $1,000,001 โ€“ $1,455,000 | $34,790 + $6.40 per $100 |
    | Over $1,455,000 | $63,910 + $4.54 per $100 |
    
    **First Home Buyer**: Full exemption up to $1,000,000 (income-tested)
    
    ---
    
    ## LMI (Lenders Mortgage Insurance)
    
    LMI is required when LVR > 80%. Estimated rates:
    
    | LVR | LMI as % of Loan |
    |-----|------------------|
    | 80.01% โ€“ 85% | 0.5% โ€“ 1.0% |
    | 85.01% โ€“ 90% | 1.5% โ€“ 2.5% |
    | 90.01% โ€“ 95% | 3.0% โ€“ 4.5% |
    
    **Example**: $600,000 loan at 90% LVR
    - LMI estimate: ~$12,000 โ€“ $15,000 (can be added to loan)
    
    > Note: Actual LMI varies by lender, LVR tier, loan amount, and borrower profile. Use lender calculators for exact quotes.
    
    ---
    
    ## First Home Owner Grant (FHOG)
    
    | State | Grant Amount | Property Cap |
    |-------|--------------|--------------|
    | NSW | $10,000 | $600,000 (new homes only) |
    | VIC | $10,000 | $750,000 (regional: higher) |
    | QLD | $30,000 | $750,000 (new homes only) |
    | WA | $10,000 | $750,000 (new homes) |
    | SA | $15,000 | $650,000 (new homes only) |
    | TAS | $30,000 | $600,000 (new homes only) |
    | NT | $10,000 | No cap (new homes) |
    | ACT | Abolished | โ€” |
    
    ---
    
    ## Borrowing Power (Quick Estimate)
    
    Basic rule of thumb:
    ```
    Max Borrowing โ‰ˆ (Annual Income ร— 6) โ€“ Existing Debts
    
    More conservative:
    Max Borrowing โ‰ˆ (Annual Income ร— 5) โ€“ Existing Debts
    ```
    
    Factors affecting actual borrowing power:
    - Income type (PAYG vs self-employed)
    - Existing debts (credit cards, HECS, car loans)
    - Living expenses (HEM benchmark)
    - Interest rate buffer (usually +3%)
    - Dependents
    
    ---
    
    ## Key Contacts
    
    - **Revenue NSW**: revenue.nsw.gov.au
    - **State Revenue Victoria**: sro.vic.gov.au
    - **Queensland Treasury**: qld.gov.au/housing
    - **WA RevenueWA**: wa.gov.au/revenuelicensing
    - **RevenueSA**: revenuesa.sa.gov.au
    - **Tasmania State Revenue**: treasury.tas.gov.au
    - **NT Treasury**: treasury.nt.gov.au
    - **ACT Revenue**: revenue.act.gov.au
    
    ---
    
    ## Disclaimer
    
    This skill provides estimates for educational purposes only. Stamp duty rates, concessions, and grants change periodically. Always verify with official state revenue offices and consult a qualified mortgage broker or financial advisor before making property decisions.
    
    **Built by [Oney & Co](https://oneyco.com.au)** โ€” Helping Australians navigate lending with clarity.