Suburb overview
Williamstown is a regional centre in South Australia, Australia, with a population of approximately 2,981, making it a boutique locality. Located approximately 39 km from the Adelaide CBD, Williamstown is a regional area in South Australia. The median household income is $92,664 per year.
Location
Key indicators
Postcode
5351
Postcode for Williamstown, from a community postcode dataset cross-checked against Australia Post. A postcode may cover multiple suburbs.
Australia Post Postcode Finder →
Population
2,981
Usual resident population at the most recent census.
Median weekly rent
$450/wk
Median weekly rent — as at Jan–Mar 2026, Consumer & Business Services (SA) (CC BY 4.0).
Distance to CBD
39 km
Straight-line distance from the suburb centroid to the nearest capital city CBD. Actual driving distance will be longer.
Housing
Median monthly mortgage
$1,500/mo
Monthly median mortgage repayment for households currently paying off a mortgage.
Home type
94% houses
Proportion of separate houses versus units, townhouses, and other home types. Useful for investors assessing rental demand mix.
Why people like living in Williamstown
- Family-friendly fringe location — around 39 km from Adelaide.
- Predominantly separate houses (94%) — suburban lifestyle with more land.
- Country-town feel with lower density and slower pace of life.
Who Williamstown suits
Pros and cons
Pros
- Rent sits within an affordable share of local incomes, supporting tenant demand.
- Mortgage costs are lower than the South Australia median, improving cash-flow margins.
- Lower purchase prices and more land for the money.
Cons
- Long distance to the CBD (39 km) — plan for commute time or local employment.
- Traffic can build during peak hours, especially on arterial roads.
Investment insight
2,981 residents places Williamstown squarely in the middle of the South Australia suburb size distribution (state median 3,699), with market depth comparable to most SA localities. Households here earn $92,664/year on average — 14% above the SA suburb median of $80,964 — a modest premium that supports resilient owner-occupier demand. Median rent of $450/week (as at Jan–Mar 2026, Consumer & Business Services (SA)) equates to roughly $1,950/month — about 130% of the $1,500/month median mortgage repayment recorded at the 2021 Census. On those figures rental income covers most or all of the recorded repayment, but repayments on new loans have risen with interest rates since 2021, so re-run the coverage at today's rates before treating this as a cash-flow suburb. At 39 km from Adelaide, Williamstown is an outer-metro location where buyers are typically trading commute time for floor space and a lower entry price. Separate houses make up 94% of dwellings — 21 percentage points above the South Australia median of 73% — pointing to a family-oriented, land-rich market where value is concentrated in the underlying block.
Investment tip
Regional property can deliver strong cash-flow yields but liquidity is tighter — plan for longer hold periods and verify local employment stability. At the 2021 Census, local rents consumed roughly 17% of household income — a dated but useful sanity check on tenant affordability.
Williamstown vs South Australia median
How Williamstown stacks up against the median of all South Australia suburbs in our dataset. Positive values mean Williamstown sits above the state median; negative means below.
| Metric | Williamstown | SA median | Δ vs state |
|---|---|---|---|
| Population | 2,981 | 3,699 | -19% |
| Median household income | $92,664/yr | $80,964/yr | +14% |
| Median rent (weekly, 2021 Census) | $300 | $320 | -6% |
| Median mortgage (monthly, 2021 Census) | $1,500 | $1,616 | -7% |
| Distance to CBD | 39 km | 13 km | +200% |
| Separate houses | 94% | 73% | +21pp |
Investor checklist
Pre-inspection briefing for Williamstown — every item is derived from public datasets, with full citations in our data sources page.
- Market depth: 2,981 residents — 81% of the SA suburb median (3,699).
- Purchasing power: median household income $92,664/year (+14% vs South Australia suburb median of $80,964).
- Cash-flow coverage (2021 Census): $300/week rent (≈ $1,300/month) covered ~87% of the $1,500/month median mortgage at the 2021 Census — verify against current rents and rates.
- CBD access: 39 km straight-line from Adelaide (state suburb median 13 km).
- Dwelling mix: 94% separate houses — house-dominant market (vs 73% state median).
- Rate stress-test: budget ~$150/month extra for a 1-percentage-point RBA rate rise on top of the $1,500/month median repayment.
- Tenant rent burden: 17% of the median household income is spent on rent — comfortably affordable.
Investment strategy
Limited buy-and-hold upside: a small population of 2,981 means liquidity is thin and capital growth tends to lag the wider South Australia market over full cycles.
Strong rental coverage at the 2021 Census: $300/week (~$1,300/month) covered 87% of the $1,500/month median mortgage, a shortfall of just $200/month. Both rents and repayments have moved since 2021 — verify current figures, though this suburb has historically leaned cash-flow-friendly.
With 94% houses in a 2,981-person market, renovation margins depend on individual street and aspect rather than any suburb-wide story — do comparable-sales analysis before committing capital.
Risk factors
- Interest-rate sensitivity: the $1,500/month median mortgage in Williamstown means a 1-percentage-point RBA rate rise could add roughly $150/month to repayments, reducing buyer borrowing capacity and cooling prices.
- Liquidity risk: with 2,981 residents, Williamstown has a thinner pool of buyers and tenants than larger suburbs. Expect longer days-on-market on resale and budget for potential vacancy gaps between tenancies.
- Williamstown is 39 km from the CBD — not close enough to benefit from the inner-ring pricing halo, so growth depends more heavily on local infrastructure decisions and the wider South Australia market cycle.
- House-dominant stock: 94% of dwellings are separate houses, so value is concentrated in land — weather events, insurance repricing and land-tax changes hit investors here more directly than in a unit-heavy suburb.
- Regulatory risk: changes to Australian tax settings (negative gearing, CGT discount, foreign-buyer surcharges, land-tax thresholds) could reshape after-tax returns in Williamstown regardless of local market conditions.
Run the numbers on a Williamstown property
Walk the journey to a place like Williamstown
Seven guided stops — government schemes compared for your exact numbers, a real budget, suburb shortlisting and every contract deadline tracked. Free, no signup to start.
Start your journey near Williamstown →2026 outlook
Capital-growth expectations for Williamstown are modest for 2026 — incomes 14% above the SA median of $80,964 and a population of 2,981 suggest gains will lag headline metro markets. At the 2021 Census, rental coverage ran at ~87% of the typical mortgage ($1,300/month rent vs $1,500/month repayment), keeping cash flow in positive or near-neutral territory. Verify against current rents and rates. Overall investor sentiment for Williamstown is cautious heading into the second half of 2026, based on its income, rent and mortgage profile relative to the South Australia median.
Frequently asked questions
Is Williamstown a good suburb for investment?
Whether Williamstown suits you depends on your strategy, but the fundamentals are concrete: a population of 2,981, a median household income of $92,664/year and median weekly rent of $300. Weigh those against your goal — cash flow, capital growth, or a value-add renovation — each of which we break down with suburb-specific ABS numbers elsewhere on this page.
What drives property demand in Williamstown?
The main demand drivers in Williamstown are an above-state-median household income of $92,664/year, a dwelling mix that is 94% separate houses. Together these shape both owner-occupier and tenant demand.
What is the population of Williamstown?
Williamstown has a usual resident population of approximately 2,981, compared with a South Australia suburb median of 3,699 — placing it in the lower half of the state's suburbs by size. Population is the clearest proxy for market depth: more residents mean more transactions and typically a shorter average days-on-market on resale.
How far is Williamstown from the Adelaide CBD?
Williamstown sits 39 km straight-line from the Adelaide CBD. This is an outer-metro location; local employment and infrastructure announcements tend to move prices more than CBD connectivity alone.
What is the median rent in Williamstown?
The median weekly rent in Williamstown is $450 (as at Jan–Mar 2026, Consumer & Business Services (SA)), equating to approximately $23,400/year in gross rental income. Confirm against current listings on realestate.com.au and Domain before making an offer.
What is the typical mortgage repayment in Williamstown?
The median monthly mortgage repayment in Williamstown is $1,500, or approximately $18,000/year (vs $1,616/month state median). Stress-test your own borrowing at rates 1–2 percentage points above today's to make sure you can still service the loan through an RBA tightening cycle.
Is Williamstown cash-flow positive for investors?
A median weekly rent of $300 works out to $1,300/month, covering 87% of the median mortgage repayment of $1,500/month. That leaves a $200/month shortfall (around $2,400/year before tax benefits), so a typical owner-occupier-priced property here is negatively geared. Actual cash flow depends on your deposit, loan terms, ownership costs and marginal tax rate — run the full numbers in our rental yield calculator.
What are the main risks of investing in Williamstown?
The main risks are a thin buyer pool (2,981 residents), interest-rate sensitivity on the $1,500 median mortgage, the broader South Australia market cycle. Each of these is covered in the Risk Factors section above with suburb-specific numbers rather than generic warnings.
How we built this Williamstown profile
The population figure on this page comes from the ABS 2021 Census. The postcode comes from a community postcode dataset cross-checked against Australia Post. The dwelling mix is from the ABS 2021 Census. The median household income is the ABS 2021 Census median weekly household income, annualised. Distance to the CBD is calculated from the suburb's ABS centroid. The Census median rent and mortgage figures are 2021 figures and are labelled as such wherever they appear — they are five years old and have moved substantially since. The current median weekly rent in Key indicators is a genuine recent figure from Consumer & Business Services (SA) (Jan–Mar 2026), published under a Creative Commons licence and dated on the page. We do not publish an investment score or school/park counts for this suburb. See our methodology and data sources for exactly what's measured and what's estimated.