Castle Green

Castle Green is a condominium in District 26 (Mandai / Upper Thomson), in the Outside Central Region. In the 12 months to August 2026, the median price was S$1,385 psf from 18 sales.

At a glance

District

District 26 (Mandai / Upper Thomson)

Region

Outside Central Region

Type

Condominium

Tenure

99-year lease from 1993, about 66 years left

Completed

1997, about 29 years old

What the prices say

The median home in Castle Green sold for S$1,574,000: the middle of 18 sales in the 12 months to August 2026.

That is well below the middle condo project in District 26 (Mandai / Upper Thomson), which sold at S$1,914 psf across 13 projects: about 28% lower. By price per square foot it ranks 8th of the 9 projects in the district that have a price to show, where 1st is the highest.

Year by year, the median was S$950 psf in 2021 (39 sales) and S$1,382 psf in 2026 so far (12 sales), up about 45%. The highest year in the record was 2025 at S$1,315 psf.

Higher floors sold for more here: floors 11 to 15 at S$1,440 psf against S$1,310 psf on floors 1 to 5, about 10% more per square foot (24 months).

By unit size (24 months): 900 to 1,199 sq ft at S$1,339 psf and 1,200 to 1,499 sq ft at S$1,347 psf. Price per square foot was similar across sizes.

Against similar projects in the district

This project and the three others in District 26 (Mandai / Upper Thomson) whose median over the last 12 months is closest to Castle Green's S$1,385 psf. They are chosen by price per square foot, not by distance, so they may not be neighbours.

Their middle figure is S$1,511 psf, so Castle Green sold noticeably below it: about 8% lower.

What sells here

18 homes sold in the last 12 months, down from 21 in the 12 months before.

The most common size was 900 to 1,199 sq ft, with 27 of the 39 sales in the last 24 months, well over half.

None of the 39 sales in the last 24 months were first sales of new units: all 39 were resales.

Rents and yield

Rental contracts that began in the 12 months to August 2026 had a median rent of S$3,600 a month (66 contracts). The district's median across every contract was S$4,000, so rents here ran noticeably below it: about 10% lower.

Over the 24 months the median rent was S$3,700 (134 contracts), about the same as the latest 12 months, within 3%.

By bedrooms: 2 bedrooms S$3,400 (40), 3 bedrooms S$4,400 (21) and 4 or more bedrooms S$5,100 (5). The figure in brackets is the number of contracts.

Setting rent against price for 900 to 1,199 sq ft homes (52 rentals and 12 resale or sub-sale transactions) gives a gross yield estimate of 3.1%: a median rent of S$3,500 a month against a median price of S$1,339,000. It is before maintenance, vacancy, tax and loan costs, and it uses middle values, so a particular home can differ.

Across 2 size ranges the estimate runs from 2.5% to 3.1%.

1,200 to 1,499 sq ft: 2.5% (rent S$4,500 a month, price S$2,155,000).

Age and lease

The title is a leasehold, so the years remaining shrink each year. The leases and tenure entry in the glossary explains what that means for a buyer.

Leases and tenure in the glossary

What this page cannot tell you

A median is the middle of many different homes in Castle Green. It does not describe one unit: its condition, facing, view, renovation, floor or stack can each move a price well away from the middle, and none of them is in the records behind this page.

The figures are recorded transactions, so they describe what has sold and not what is on the market now. They are not a valuation, and they say nothing about future prices.

Questions this page answers

What is the median price per square foot in Castle Green?

S$1,385 psf in the 12 months to August 2026, from 18 sales. For the median home that is S$1,574,000.

How many homes sold in Castle Green?

18 in the last 12 months and 39 in the last 24 months, across all sale types.

What do homes in Castle Green rent for?

The median rent for contracts that began in the 12 months to August 2026 was S$3,600 a month, from 66 contracts.

What is the rental yield in Castle Green?

Between 2.5% and 3.1% gross, depending on unit size. It is an estimate before costs, made from the median recorded rent and the median resale or sub-sale price for each size range.

How much lease is left in Castle Green?

It is a 99-year lease from 1993, which leaves about 66 years at 2026.

Figures from URA data, 12 months to August 2026. Rents to August 2026. General information, not financial advice.

The figures

Sale prices

Source: URA data. Data as of August 2026.

Price by year

Each year is the median over the sales recorded in it. Source: URA data. Data as of August 2026.

Price by floor range

Price by unit size

The floor is the storey recorded in each sale. Source: URA data. Sales in the 24 months to August 2026. Data as of August 2026.

Rent against price for Castle Green, by size

Rents

Source: URA data, rental contracts. Rents are the median of the contracts that began in the period. Data as of August 2026.

Where to look next

• Work out the stamp duty on a purchase at these prices (Free, no sign-in)
• How buyer stamp duty works
• Loan limits: how much a bank can lend
• The cooling measures, including additional stamp duty
• Other condos in District 26 (Mandai / Upper Thomson)
• Rents for every district, by size
• Rent against price for Castle Green, by size
• Leases and tenure in the glossary

Other condos in District 26 (Mandai / Upper Thomson)

• Green Meadows
• Hillock Green
• Hong Heng Garden
• Hong Heng Mansions
• Lentor Central Residences
• Lentor Hills Residences
• Lentor Mansion
• Lentoria
• Meadows @ Peirce
• Roots @ Transit
• Seasons Park
• Springleaf Residence

About the data

Figures are medians of transactions recorded by URA, over the periods shown, and a figure appears only when at least 5 records sit behind it. Sale figures: data as of August 2026. Rent figures: data as of August 2026. Swee Homes is not affiliated with URA or Condo Atlas. General information, not financial advice.