
Situated within The Island, one of Austin’s most coveted gated communities on Lake Austin, this exceptional waterfront estate offers a rare combination of privacy, acreage, and direct lake access. Set on 1.6 acres along a serene canal, the property includes a spacious main residence and a separate one-bedroom guest house, creating an ideal setting for both everyday living and hosting family and friends. Designed for effortless entertaining, the main home features an open floor plan that connects expansive living spaces with the outdoors. Large windows frame peaceful water views, while the covered patio with a fireplace provides a year-round gathering space overlooking the property’s lush surroundings. Five bedrooms, four full bathrooms, and two half bathrooms offer flexibility and comfort across the thoughtfully designed residence. Outdoor amenities elevate the Lake Austin lifestyle, with a private dock featuring two boat slips for easy access to boating, paddleboarding, and waterfront recreation. Combining the security and prestige of The Island with generous acreage, guest accommodations, and coveted waterfront access, this property presents a rare opportunity to experience one of Austin’s most desirable lakefront settings. Tax and assessed values are estimates for illustration purposes only. All figures should be independently verified.
Property Type
Residential
Year Built
1996
Lot Size
1.60 acres
$/Sq Ft
$754
HOA
$3000/mo
Garage
3 spaces
Listed by Moreland Properties
Property Details
Features
Appliances
Flooring
Features
Construction
Lot Features
Fencing
Foundation
Patio / Porch
Parking
Waterfront
Verified property facts
4400 Island Ave is listed at $6,500,000 with 5 bedrooms, 4 full, 2 half bathrooms, 8,626 square feet, 1.60-acre lot. This places it above the 78731 median of $1,225,000.
4400 Island Ave is zoned for Austin ISD with assigned schools: Highland Park (elementary), Lamar (Austin ISD) (middle), McCallum (high). School assignments should be verified directly with the district.
4400 Island Ave is a Residential built in 1996 featuring 5 bedrooms, 4 full, 2 half bathrooms, 8,626 square feet, 1.60-acre lot.
4400 Island Ave is presented by the Keenan Group at Compass Real Estate, the #1 Austin Board of Realtors Team (2024) with 1,000+ career transactions and $1B+ in career volume across Austin's luxury market.
The most recent annual property tax for 4400 Island Ave is $114,304. Texas has no state income tax, so property taxes are a primary revenue source. Rates vary by jurisdiction and exemptions. Verify current amounts with the county appraisal district.
#1 Austin Board of Realtors Team. Over 1,000 successful transactions with high-end expertise.
25+ years advising buyers and sellers in this community
Listed with current price, original ask, and market time.
Public record data from county appraisal records. Market value can differ from assessed value.
| Year | Taxes | Total Assessment | Land | Additions |
|---|---|---|---|---|
2025+22.0% | — | $5,585,378 | — | — |
2024-10.0% | — | $4,579,397 | $4,436,775 | $1,605,901 |
2023+11.2% | — | $5,088,149 | $2,673,000 | $1,906,397 |
2022+22.6% | — | $4,575,831 | $2,673,000 | $2,415,149 |
2021 | — | $3,733,400 | $2,673,000 | $1,902,831 |
Zoned assignments come from the property school fields available to us. District context schools are shown only when an assigned tier is missing. Contact the school district directly to verify current boundaries and enrollment eligibility. Ratings from GreatSchools.org.
20% ($1.3M)
$6,500,000
Luxury property intelligence
A sourced read on Island At Mount Bonnell Shores pricing, timing, and property scale. No automated valuation claim.
List price
$6,500,000
Price per sqft
$754/sqft
Vs. Island At Mount Bonnell Shores median
Not available
Days on market
24 days
Original to current
No verified reduction
$6.5M original
Active inventory context
Ask for current inventory
Source: MLS Grid / Unlock MLS and Keenan Group review as of Jul 25, 2026.
Request Private Market AnalysisZIP-level neighborhoods, schools, lifestyle, and Austin market context
District guide, nearby schools, and homes by attendance area
Private Austin CMA, TCAD context, and pricing strategy
Pricing, prep, launch timing, and Compass marketing strategy
#1 ABOR Team 2024 with $1B+ career sales volume
With 20% down ($1,300,000) on a 30-year fixed mortgage at approximately 6.75%, the estimated monthly payment for 4400 Island Ave is around $43,252 including principal, interest, and estimated taxes. Actual payment varies by rate, down payment, insurance, and HOA fees.
At $6,500,000, 4400 Island Ave is in the Island At Mount Bonnell Shores market where there are currently 54 active listings in 78731. The Keenan Group has completed 107 transactions in 78731 as part of 1,000+ career sales totaling $1B+ across Austin.
4400 Island Ave includes verified waterfront access: Canal Front,Lake Front. Buyers should confirm shoreline, dock rights, and floodplain status during due diligence.
4400 Island Ave sits on a 1.60-acre lot, providing substantial outdoor living space. Properties of this scale in Austin's luxury market typically feature pool areas, outdoor kitchens, and mature landscaping. Confirm specific amenities with the listing agent.
4400 Island Ave is part of a managed community with HOA dues of $3,000 annually. HOA-managed communities in Austin's luxury market typically provide amenities such as common areas, security, and exterior maintenance. Verify current dues and rules with the HOA directly.
Answers use visible listing facts, school context, and neighborhood data available on this page. Verify time-sensitive details before making decisions.
Car-Dependent
No Nearby Transit
Somewhat Bikeable
Walk Score measures walkability based on distance to amenities. Transit Score measures public transportation access. Bike Score measures bikeability based on bike infrastructure and terrain.
7 events on record
Current Price
$6,500,000
Timeline data compiled from MLS records and public records. Information deemed reliable but not guaranteed.
| Year | Taxes | Total Assessment | Land | Additions |
|---|---|---|---|---|
2025+22.0% | — | $5,585,378 | — | — |
2024-10.0% | — | $4,579,397 | $4,436,775 | $1,605,901 |
2023+11.2% | — | $5,088,149 | $2,673,000 | $1,906,397 |
2022+22.6% | — | $4,575,831 | $2,673,000 | $2,415,149 |
2021 | — | $3,733,400 | $2,673,000 | $1,902,831 |
Timeline merges MLS activity (when permitted) with public records. Some details may be restricted to registered VOW clients.
Best Match
Balanced against price, location, and layout so nearby lookalikes rise first. Similar properties in Island At Mount Bonnell Shores
Recent sales for market context