The real cost to build a villa on Koh Samui, per square metre

The cost to build a villa on Koh Samui is roughly ฿25,000 to ฿40,000 per square metre for a good mid-range house, and ฿45,000 to ฿60,000-plus per square metre for a luxury one. Those rates cover the building only. They exclude the pool, the land, the retaining walls, the driveway, the utility connections, the professional fees and the furniture — and that is where budgets actually break.

We are a developer, not an agency. We are building three villas at Villa Prestige in Maenam right now, and we built and still operate Sasipimon Villa in Chaweng Noi. So rather than repeat a range we found on someone else's website, this article publishes the measurements and the price tiers from our own drawings, and shows what the per-square-metre number does and does not tell you.

What does it cost to build a villa on Koh Samui in 2026?

The bands quoted across the island's builders are consistent enough to be useful. A Thai-standard house runs about ฿18,000–฿25,000 per m². Western-standard mid-range is ฿25,000–฿40,000. Premium and luxury starts around ฿40,000 and runs past ฿60,000. One Samui design practice publishes ฿60,000 per m² as its luxury base rate, excluding land, loose furniture and permits.

Those numbers are moving upwards. Thailand's Construction Materials Price Index reached 113.8 in May 2026, up 7.2% year on year, according to the Trade Policy and Strategy Office. In April it hit a 44-month high. Electrical and plumbing equipment rose 13.5%, concrete products 9.5%, steel products 5.4%. Krungsri Research puts materials at roughly 45–50% of a construction project's total cost, labour at about 30%. Do that arithmetic and materials inflation alone added about 3.2–3.6% to a build cost over twelve months — on a ฿7M construction contract, somewhere between ฿230,000 and ฿255,000.

That is worth knowing if you are comparing a quote from last year against one from this month. It is not a reason to panic. It is a reason to ask when a fixed price was fixed, and what happens to it if steel moves again.

Which square metres are you actually being quoted for?

This is the part almost nobody explains, and it is worth more than the rate itself. "Per square metre" is meaningless until you know which area is in the denominator — enclosed floor area, covered area including terraces, or gross area including the pool deck and car park.

Take our Villas 2 and 3 at Maenam, which are the same house on two different plots. From the drawings: 11.81 m² enclosed at ground level, 132.21 m² enclosed on the upper level — 144.02 m² enclosed in total. Plus an open-sided living and kitchen pavilion of 91.85 m². Covered area total: 235.87 m².

One house. At the same ฿30,000 per m², a builder quoting on enclosed area gives you ฿4,320,600 and a builder quoting on covered area gives you ฿7,076,100. That is a ฿2.76M gap — 64% — with no disagreement about the rate, the specification or the building.

The effect scales. Sasipimon Villa in Chaweng Noi, which we completed in April 2019 and still run, has 834 m² of interior, 314 m² of terraces, a 96 m² pool and 210 m² of car park. Priced on interior alone, ฿30,000 per m² gives ฿25.0M. Priced on interior plus terraces, the same rate gives ฿34.4M. Nothing about the building changed.

So the first question to any Samui builder is not "what is your rate?" It is "show me the area schedule you applied it to." A cheap-looking rate on a generous denominator is more expensive than an expensive-looking rate on a strict one.

What the per-square-metre price never includes

The headline rate typically buys the reinforced concrete structure, roof, walls, waterproofing, standard electrics and plumbing, standard tiling and paint, standard windows and doors, and the bathrooms and kitchen. Everything below is separate, and on a Samui plot it is not a rounding error:

• The swimming pool. Ours at Villas 2 and 3 is a 10 × 4 m lit overflow pool — a separate structure with its own engineering, plant room and running cost.
• External works: retaining walls, driveway, drainage, boundary walls, landscaping. On a sloping plot this line can rival the house.
• Professional fees — architect, engineer, quantity surveyor, permit submissions.
• Utility connections. Mains water and grid power do not reach every plot on this island. Our own villa in Chaweng Noi runs a deep well with 30,000 litres of storage, 77 solar panels across two 15 kW inverters, and a 100 kW automatic generator. None of that is in a per-square-metre construction rate.
• Furniture and appliances. On our Maenam villas the difference between the unfurnished and the specified-furniture tier is ฿4M.
• Contingency. Ask what the contract does when a price moves, and who carries it.

Why building on Samui costs more than the Thai mainland

Three reasons, and the first is measurable to the baht. Under the current Wage Committee minimum wage announcement, Koh Samui district sits in the top national band at ฿400 a day. Every other district in its own province — Surat Thani — is at ฿352. The statutory wage floor on this island is 13.6% higher than on the mainland twenty kilometres away. Skilled trades are paid well above the floor, but the floor sets the base.

Second, logistics. Cement, steel, tiles, glazing and sanitaryware come across on a barge. One Thai builder puts the Samui uplift at about 5–10% over Phuket, and Koh Phangan at 8–15%. Concrete has to be scheduled around the ferry, not around the site.

Third, labour supply. Krungsri Research describes construction labour shortages as a structural problem for the Thai industry, with contractors competing against manufacturing and services for both skilled Thai staff and migrant workers, a situation worsened by the Cambodian border dispute. An island a two-hour boat trip from the mainland feels that competition more, not less.

What our own villas price at, per square metre

Here are our published prices divided by our published areas. These are sale prices, not construction costs — read the next section before you use them as a build benchmark.

• Villa 2 / Villa 3, house only, no plot, unfurnished — ฿25M. That is about ฿106,000 per m² of covered area, or about ฿174,000 per m² of enclosed area.
• Villa 2 / Villa 3, house and plot, unfurnished — ฿28M. Turnkey with plot and the specified furniture — ฿32M.
• Villa 1, our completed villa: 437.33 m² enclosed across a main level, a guest level, a gym pavilion and a maid's house. ฿55M with furniture and without the plot — about ฿126,000 per m² enclosed. ฿62M turnkey with the 1,942.92 m² plot.

Note the spread. Same developer, same island, same year, same build programme — and ฿126,000 against ฿174,000 per enclosed square metre. Part of that is the denominator again: Villa 2 puts 91.85 m² of its living space in an open-sided pavilion that never counts as enclosed floor. The rest is scale. The pool, the driveway, the connections, the design and the permits cost roughly the same whether the house is 144 m² or 437 m², so a larger villa carries them more cheaply per square metre. That is the single most reliable rule in villa budgeting, and it works against small houses.

What does the land actually cost?

We can give you a real answer, because we sell the same house with and without its plot and the difference is arithmetic. Villas 2 and 3: ฿28M with the plot, ฿25M without — ฿3M for 811.09 m² and 861.82 m² respectively, so ฿3,700 and ฿3,480 per m². Villa 1: ฿62M turnkey against ฿55M without the plot — ฿7M for 1,942.92 m², or ฿3,600 per m².

Three separate plots, all landing between ฿3,480 and ฿3,700 per square metre — roughly ฿5.6M to ฿5.9M per rai. Which means land is about a tenth of our turnkey price: 9.4% on Villa 2, 11.3% on Villa 1. Buyers routinely assume the plot is the dominant cost on an island. On inland Maenam it is not. Sea-view and beachfront land is a different market entirely, running to ฿10M and well beyond per rai, and that is where the ratio inverts.

The honest limitation

Everything above is a price, not a cost. Our sale price contains the construction contract, the land, the pool, site works, design, permits, infrastructure, marketing, warranty provision and our margin. We are not publishing our contractor's bill of quantities or our margin, and any developer who claims to be is selling you something. What we can do is show the drawings, the area schedule and the tier structure, so you can see exactly what each number is measured against.

Two further caveats. This is three villas by one developer on one inland Maenam site — a hillside plot with retaining walls, a long access road and a transformer to install is a different exercise, and slope, height and beach-setback rules on Samui restrict what can be built at elevation. And a one-off self-build costs more per square metre than a villa built inside a three-house programme, because you carry the design, the permits and the site setup alone.

How much does it cost to build a villa on Koh Samui per square metre?

About ฿18,000–฿25,000 per m² for basic Thai-standard construction, ฿25,000–฿40,000 for good mid-range, and ฿40,000–฿60,000-plus for luxury. These cover the building shell and standard finishes only — not the pool, land, site works, fees or furniture.

Is it cheaper to build a villa on Samui than to buy one?

On paper, sometimes. In practice you take on the land search, the permits, the contractor risk, the currency exposure and 18–24 months of your own time, and you lose the per-square-metre advantage a multi-villa programme gets on fixed costs. Building is cheaper if you can manage the project properly; if you cannot be on the island regularly, it usually is not.

Why is construction more expensive on Koh Samui than in mainland Thailand?

Three reasons: the statutory minimum wage on Koh Samui is ฿400 a day against ฿352 in the rest of Surat Thani province, materials arrive by barge with roughly a 5–10% logistics uplift over Phuket, and skilled labour is scarcer on an island.

How much of a villa's price is the land?

On our own inland Maenam plots, about 9–11% of the turnkey price — around ฿3,500–฿3,700 per square metre of land. Sea-view and beachfront plots cost several times that, so the proportion changes completely depending on where you buy.

Are construction costs in Thailand still rising in 2026?

Yes. The Construction Materials Price Index stood at 113.8 in May 2026, up 7.2% year on year, and the Trade Policy and Strategy Office expected further increases on energy, freight and tight global supplies of copper, steel and aluminium.