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Thornleigh

NSW 2120LGA: Hornsby Shire

Investment Score

78

/100

AI Intelligence Summary

Thornleigh is an established family-oriented suburb located 25km northwest of Sydney CBD in the Upper North Shore region. With a population of 8,200 and median age of 42, it attracts professionals and families seeking quality education, transport connectivity, and a balanced lifestyle. The suburb features predominantly detached houses (72%) on generous blocks with a median land size of 680sqm. Thornleigh Railway Station provides direct CBD access via the T1 Northern Line, while proximity to quality schools including Thornleigh Public School and Normanhurst Boys High School drives strong demand. The median house price of $1,450,000 reflects its desirable location, though it remains more affordable than premium North Shore suburbs. Community amenities include Thornleigh Marketplace, recreational facilities at Thornleigh Oval, and close access to Ku-ring-gai Chase National Park. With 45% professional workers, 42% university-educated residents, and strong infrastructure connectivity, Thornleigh represents a well-established suburb offering family-friendly living with solid investment fundamentals and consistent growth potential in the competitive North Shore market.

Strengths

  • Direct train access to Sydney CBD via T1 Northern Line
  • Proximity to highly-rated public and private schools
  • Established family-friendly community with quality amenities
  • Close to national parks and recreational facilities

Opportunities

  • Potential for house renovations and extensions on large blocks
  • Growing demand from families seeking North Shore education
  • Infrastructure improvements benefiting broader region
  • Increasing appeal as affordable North Shore alternative

Considerations

  • Limited new development opportunities due to established nature
  • Competition from premium North Shore suburbs
  • Moderate rental yields compared to other investment areas
  • Distance from beach and coastal amenities

Property Market

Median House

$1.45M

+4.2% 1yr

Median Unit

$680K

+3.8% 1yr

Median Townhouse

$950K

Rent (House)

$890/wk

Rent (Unit)

$535/wk

Days on Market

42

Vacancy Rate

1.8%

Auction Clearance

72.0%

Price Growth

Type1 Year3 Year5 Year
House+4.2%+18.5%+35.8%
Unit+3.8%+16.2%+32.1%

Rental Yields

House Yield

3.2%

Unit Yield

4.1%

Townhouse Yield

3.5%

Investment Scorecard

Overall Investment Score78/100
Growth Potential75/100
Cashflow Score68/100
Risk Score (lower = safer)72/100
Affordability Index65/100

Demand/Supply Ratio: 1.40

Demand exceeds supply — favourable for sellers

Tax & Financial Intelligence

CPA-grade analysis for Thornleigh at median house price

Standard transfer
$62,140
First Home Buyer
$62,140
Foreign buyer surcharge
$116,000

+8% surcharge

Annual rent income
$46,280

$890/wk

Interest (80% LVR @ 6.5%)
-$75,400
Other expenses (~2.5%)
-$36,250
Net rental position
-$65,370

Negatively geared

Tax benefit (39% MTR)
+$25,494

Reduces taxable income

After-tax holding cost
$39,876/yr

~$767/week

Based on 7.2% p.a. growth (from 5-year trend), 50% CGT discount, 39% MTR

5-Year Hold

Est. value
$2.05M
Capital gain
$529,561
After discount
$264,780
CGT payable
$103,264

10-Year Hold

Est. value
$2.90M
Capital gain
$1.38M
After discount
$687,960
CGT payable
$268,304

Investor Quick Summary

Entry cost (stamp duty)

$62,140

After-tax yield

1.95%

Weekly holding cost

$767/wk

10yr CGT (est.)

$268,304

Estimates based on FY2025 NSW rates at median house price. Assumes 80% LVR, 6.5% interest rate, 39% marginal tax rate ($135K-$190K bracket). Individual circumstances vary. This is general information only and not personal financial advice. Consult your CPA before making investment decisions. Local Knowledge Pty Ltd — Registered Tax Agent.

Demographics

Population

8,200

Median Age

42

Median Income

$95K

per annum

Family Households

58.0%

Professionals

45.0%

University Educated

42.0%

Unemployment

3.2%

Born Overseas

38.0%

Dwelling Mix

Houses: 72%Units: 23%Townhouses: 5%Total: 3,200

Lifestyle & Community

Walkability65/100
Public Transport8/10
Schools Rating8/10
Safety8/10
Family Friendly9/10
Cafes & Restaurants

18

Parks

12

Hospitals

1

Distance to CBD

25.0 km

Nearest Station: Thornleigh Railway Station

Family-friendly lifestyle with access to parks, recreational facilities, quality schools, and convenient transport to Sydney CBD while maintaining suburban tranquility.

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Data sourced from multiple sources. Last updated 29 March 2026.

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