Clontarf vs Seaforth: true annual running costs compared (2026)
Last updated July 2026 · council rates current NSW schedules, ATO 91c/km, Opal & Translink fares, AER electricity benchmarks
Clontarf and Seaforth are both Northern Beaches rates (OLG suburbs, sitting 8.1 km and 8.6 km from Sydney CBD respectively, and are commonly compared by buyers weighing up running costs within the same council area.
Seaforth runs $312 a year cheaper than Clontarf, driven mostly by home insurance. Over 10 years at 3% growth that gap compounds to about $3,576.
Over 10 years these two cost about the same to run. The difference here isn't money — it's location, schools and lifestyle.
Get the free report: 10-year costs, flood & fire risk, crime, schools and overall verdict →Clontarf
Seaforth
Annual cost breakdown
| Category | Clontarf | Seaforth | Difference |
|---|---|---|---|
| Council rates | $1,766 | $1,766 | - |
| Water & sewerage | $1,548 | $1,548 | - |
| Commute (driving) | $2,544 | $2,682 | -$138 |
| Commute (public transport) | $1,920 | $1,920 | - |
| Home insurance | $2,600 | $2,150 | +$450 |
| Body corporate (unit) | $2,600 | $2,600 | - |
| Total (driving) | $8,458 | $8,146 | +$312 |
| Total (public transport) | $7,834 | $7,384 | +$450 |
Green = cheaper. Commute: ATO 91c/km, 220 working days. Insurance AI-estimated; actual premiums vary. Council rates: average residential rate (NSW, IPART-uplifted).
| Dwelling | Clontarf | Seaforth | Difference |
|---|---|---|---|
| House | $2,342 | $2,342 | - |
| Unit | $1,909 | $1,909 | - |
Estimated from AER residential benchmarks for each suburb's climate zone at 2026-27 regulated prices for each suburb's electricity network, including supply charge (AER Default Market Offer caps, or the QCA price in regional Queensland; unit ≈ 75% of a house). Get the free report for a breakdown by your exact number of occupants.
Cost breakdown chart
Annual cost breakdown — Clontarf vs Seaforth (2026-27)
What the numbers show
Seaforth costs $312 less per year to run by car. Held over ten years at 3% annual cost growth, that gap compounds to $3,576 in favour of Seaforth.
The biggest single gap is home insurance at $450 per year. Clontarf carries medium flood risk, which pushes estimated premiums higher.
On public transport the gap is $450 per year, $7,834 from Clontarf versus $7,384 from Seaforth.
Where the difference actually comes from
- Council rates is identical at $1,766 a year.
- Water and sewerage is identical at $1,548 a year.
- Driving commute favours Clontarf by $138 a year, $2,544 against $2,682.
- Building insurance favours Seaforth by $450 a year, $2,150 against $2,600.
Both suburbs sit in the same council area, so the rates line is identical and none of the difference between them comes from council. What separates them is commute distance and the insurance band.
Flood risk is rated medium in Clontarf against low in Seaforth, which feeds the insurance estimate.
10-year cumulative cost projection
| Year | Clontarf cumulative | Seaforth cumulative | Difference |
|---|---|---|---|
| Year 1 | $8,458 | $8,146 | $312 |
| Year 3 | $26,143 | $25,178 | $965 |
| Year 5 | $44,905 | $43,248 | $1,657 |
| Year 10 | $96,961 | $93,385 | $3,576 |
Assumes 3% annual cost growth. Excludes purchase price, mortgage, and personal expenses.
Frequently asked questions
Is Clontarf or Seaforth cheaper to live in?
Seaforth is cheaper to run by car at $8,146 per year versus $8,458 for Clontarf, a difference of $312 annually. Figures cover council rates, water, commute (ATO 91c/km), and home insurance. Source: SuburbCost 2026 data.
What are council rates in Clontarf and Seaforth?
Annual council rates for a house are $1,766 in Clontarf (Northern Beaches rates (OLG) and $1,766 in Seaforth (Northern Beaches rates (OLG). Water and sewerage adds $1,548 in Clontarf and $1,548 in Seaforth. Both figures are the average residential rate reported to the Office of Local Government, uplifted by each council's IPART rate peg.
How does the commute cost compare between Clontarf and Seaforth?
Annual driving commute costs are $2,544 from Clontarf and $2,682 from Seaforth to Sydney CBD (ATO 91c/km). Public transport costs $1,920 from Clontarf and $1,920 from Seaforth.
What is the 10-year cost difference between Clontarf and Seaforth?
At 3% annual cost growth, Clontarf costs a cumulative $96,961 and Seaforth costs $93,385 over 10 years by car. The cumulative difference is $3,576 in favour of Seaforth. Excludes purchase price, mortgage, and personal expenses.
Which of Clontarf and Seaforth is best to actually live in?
You've got the costs. Get the free personalised report for the rest: a clear verdict on which suburb wins, the full flood, fire and crime risk profile, nearest schools, estimated electricity cost by number of occupants, and your own loan or rent stress-tested over 10 years. No spam.
Related comparisons
Sources: Northern Beaches rates (OLG and Northern Beaches rates (OLG rate data, water utility pricing (QLD: Queensland Urban Utilities / Unitywater; NSW: Sydney Water / Hunter Water), ATO 91c/km, and SuburbCost AI insurance estimates. Data updated July 2026.