New South Wales · Postcode 2099
Dee Why postcode and suburb data
New South Wales · Phone area code 02 · 15 km from Sydney
Suburb snapshot
Dee Why at a glance vs NSW
Fast facts and benchmark bars show the suburb's key postcode, Census, SEIFA, school and LGA signals in context.
Quick facts
Benchmarks against NSW
Income, rent and SEIFA figures are from the ABS 2021 Census and are reported in 2021 dollars, not adjusted for subsequent inflation.
Where Dee Why ranks: household income is in the top 25% of NSW suburbs; rents are among the top 10% in NSW; SEIFA decile 9 puts it in the top 20% of Australia for socio-economic advantage.
ABS Census 2021 · SEIFA 2021Detailed comparison table
Dee Why vs the NSW average and the national average, using population-weighted 2021 Census data.
| Metric | Dee Why | NSW avg | AU avg | Greater Sydney |
|---|---|---|---|---|
| Household income/wk | $2,106 ≈NSW | $1,931 | $1,836 | $2,181 |
| Rent/wk | $550 +NSW | $445 | $390 | $506 |
| Mortgage/month | $2,457 ≈NSW | $2,247 | $1,958 | $2,587 |
| Median age | 36 | 45.0 | 45.0 | 39.0 |
| SEIFA decile | 9/10 +NSW | 6.0/10 | 6.0/10 | 10.0/10 |
| Unemployment | 3.7% -NSW | 5.0% | 5.0% | 5.0% |
Green pill = at least 10% above the NSW average; red = at least 10% below; grey = within 10%. For unemployment, colour polarity is inverted: lower is better.
Dee Why is a coastal suburb of Sydney in New South Wales, with postcode 2099. It sits about 15 km from the Sydney CBD, within the Northern Beaches local government area. The suburb footprint covers roughly 3.1 square kilometres.
According to the 2021 Census, Dee Why has a population of 23,354 with a median age of 36. The median weekly household income is $2,106, close to the NSW average. The unemployment rate is 3.7%, lower than the NSW average. The Indigenous population is 162 (0.7% of residents).
Housing in Dee Why includes a median weekly rent of $550, median monthly mortgage repayment of $2,457, with 9,863 total dwellings. These housing costs sit above the NSW average. Rental properties account for 48.5% of dwellings.
On the SEIFA Index of Relative Socio-economic Advantage and Disadvantage, Dee Why scores in decile 9 out of 10, which is well above the national average.
There are 4 schools in the Dee Why area, including St Luke's Grammar School, Dee Why Public School, St Kevin's Catholic Primary School and others.
Dee Why is part of the Warringah statistical area in New South Wales.
Dee Why details
Location, Census, housing, SEIFA and geography fields used across this profile.
| Postcode | 2099 |
| State | New South Wales (NSW) |
| Phone Area Code | 02 |
| Population (2021) | 23,354 |
| Median Age | 36 years |
| Median Household Income (Census 2021) | $2,106/week |
| Median Personal Income (Census 2021) | $1,065/week |
| Median Weekly Rent (Census 2021) | $550 |
| Median Monthly Mortgage (Census 2021) | $2,457 |
| Average Household Size | 2.3 persons |
| Area | 3.1 km² |
| Population Density | 7573/km² |
| Total Dwellings | 9,863 |
| Australian Citizens | 74.2% |
| Indigenous Population | 162 (0.7%) |
| Unemployment Rate | 3.7% |
| SEIFA IRSAD Decile | 9/10 (well above average) |
| Latitude | -33.7544 |
| Longitude | 151.2854 |
| Distance from Sydney | 15 km |
| Region (SA4) | Sydney - Northern Beaches |
| Area (SA3) | Warringah |
| Local Government | Northern Beaches |
| Federal Electorate | Mackellar |
| State Electorate | Wakehurst |
| Time Zone | AEST (UTC+10), Australia/Sydney (standard time) |
Age Profile
Show counts
| 0–14 years | 3,505 (15.0%) |
| 15–24 years | 2,328 (10.0%) |
| 25–44 years | 9,128 (39.1%) |
| 45–64 years | 5,581 (23.9%) |
| 65+ years | 2,806 (12.0%) |
Housing Tenure
SEIFA socio-economic index
Health Conditions (2021 Census)
| Asthma | 1,471 (6.3%) |
| Arthritis | 1,227 (5.3%) |
| Diabetes | 685 (2.9%) |
| Heart Disease | 579 (2.5%) |
| Cancer | 492 (2.1%) |
| Lung Condition | 188 (0.8%) |
| Dementia | 92 (0.4%) |
Long-term health conditions self-reported in the 2021 Census. Persons may report more than one condition.
Motor Vehicles per Dwelling
| No vehicle | 1,101 (11.3%) |
| 1 vehicle | 5,054 (52.1%) |
| 2 vehicles | 2,726 (28.1%) |
| 3+ vehicles | 827 (8.5%) |
Schools in Dee Why
ACARA 2025 school profiles for schools located in Dee Why. ICSEA is shown where ACARA publishes it.
Suburbs Near Dee Why
Same Postcode (2099)
More Dee Why Data
Page last reviewed . Data sources: Australian Bureau of Statistics 2021 Census (CC BY 4.0), SEIFA 2021 IRSAD, ACARA school profiles 2025. How this data is sourced.