The Patong Tunnel Is Good News However, It Won’t Fix the Two Roads the West Coast Actually Sits On.

The Phuket expressway was back in the news this week. On 16 September the government said the Kathu to Patong tunnel goes to Cabinet in December, with an opening targeted for October 2031. It is good news and I am glad to see it. It also does nothing for the two roads I sit on most weeks, which are the ones that matter if you are buying or selling on the west coast.

I will take the announcement first, then the roads, then what I think it means for property either side of it.

What the Phuket expressway announcement said

Phase 1 is the Kathu to Patong link: 3.98 kilometres, of which 1.85 kilometres is tunnel, at a cost of about ฿16.8 billion. The timetable given is Cabinet in December 2026, a contractor chosen around April 2027, construction from October 2027 and opening in October 2031. The tunnel has been narrowed from 17 metres to 14 to bring the cost down, and the opening toll has been cut to ฿20 for a car. The government says it turns a 30 minute drive over the hill into five.

Phase 2 is the big one. It runs 30.62 kilometres from Mueang Mai near the airport, through Koh Kaew, to Kathu, at an estimated ฿67.5 billion. The Expressway Authority expects to seek Cabinet approval for it in 2027 and is still working on forest land permits. Its own governor has called it the harder sell financially.

2031 is a target, not a date

This project has been talked about for more than a decade, and the targets have a habit of moving. In 2021 the tunnel was reported as due by 2028. Last October the reported target was April 2030. This week it is October 2031. Every one of those was said in good faith.

I am not knocking it. The land is reported as almost fully acquired and the redesign is a sign someone is trying to make the numbers work. But a Cabinet submission is not an approval, and an approval is not a road. If someone quotes you a drive time that depends on 2031, treat it as a hope.

The two roads that are actually choking

Here is the part the announcement does not touch. If you live or work on this coast, two roads decide your day, and both run from Thepkrasattri Road down to the sea.

The first is Srisoonthorn Road. It leaves the Robinson junction by the Heroines Monument and runs down through Cherng Talay to Surin and Kamala. The second is the Ban Don to Cherng Talay road, which comes down from Thalang and brings you out at Porto de Phuket, Boat Avenue, Laguna and Bang Tao. They meet in Cherng Talay, and between them they carry almost everyone heading for this stretch of coast.

In peak season both are wild. They back up badly on the school run and again between about four and six in the afternoon. I have watched them get busier every year, and they get busier each time another building fills up, because everyone in those buildings is heading the same way: down to the coast.

The Patong tunnel is about fifteen kilometres south of that problem. It will be a relief for Patong and Kathu. It does not add a single lane between Thepkrasattri Road and these beaches.

The affordability belt

The reason those roads keep filling is simple. The coast has priced people out. Bang Tao and Layan now belong to villas and branded residences, and a lot of people who want this part of the island cannot afford to live that close to the sand any more. So they are moving a few kilometres inland, to Si Sunthon and to places like Pru Jampa that look far from the coast on a map and are not, once you know the back roads into Boat Avenue and Bang Tao.

I call it the affordability belt, and the supply is arriving. One example: a 411 unit condominium sits on Srisoonthorn Road, under a kilometre from the Robinson junction. I met the team last week and the buildings are nearly finished. Close by on Thepkrasattri Road, the Vanich family’s CV Group has announced Synthesis Ark: 491 rai, a stated ฿50 billion, with condominiums, villas, offices, hotels, schools and retail, and full completion targeted for 2032. Those are the developer’s figures, and a masterplan is not a building. But a family that has held that land for generations has decided now is the time.

From the belt you are 15 to 30 minutes from Bang Tao depending on the hour. That is my own drive, not a brochure number. The demand here is driven by affordability, and it is meeting a real need.

What Phase 2 does, and does not do

Phase 2 runs north to south, roughly parallel to Thepkrasattri Road, and relieving that road is its stated job. The jams I am describing run east to west. So the honest answer is: it helps at the top of each road and nowhere else.

The detail worth knowing is in the Expressway Authority’s own design. It shows an exit on each of my two roads: a Ban Don interchange on the Ban Don to Cherng Talay road, and a Manik interchange on Srisoonthorn Road, with a ramp for traffic turning towards Surin. If they are built, a driver from the airport or from the south skips Thepkrasattri Road and the Robinson junction altogether and drops straight onto the road they need. Those junctions may finally breathe.

Then the same cars, or more of them, arrive on the same two roads with the same number of lanes. Nothing in either phase adds capacity between the exits and the beach.

What it means for a buyer

Buy the drive you can do today. Do it yourself at 8am and at 5pm in high season before you commit. If it works now, 2031 is a bonus.

The belt is a price decision. You are trading minutes for baht. That is a good trade for plenty of people. It is a different asset from a coastal one, and as I wrote in the 19 months of stock piece, condominium supply is where this market is deepest, so choose the building carefully.

Ask where the access comes from. Which road, which junction, and what is being built along it in the next three years. Nobody will volunteer this. You check it yourself.

What it means for an owner

If you own on the coast, access is becoming part of your value. A villa that reaches the beach and the village without touching either of those roads has an advantage that did not matter five years ago, and your listing should say so. The belt is also not your competition. It is where many of your future tenants, staff and eventual buyers will live first.

If you own in the belt, your buyer is price-led and practical. Sell the honest drive time and the back roads, not the expressway.

The read

The tunnel is real progress for Patong, and I hope it opens on time. The west coast’s problem is two different roads, the relief for them is a pair of exits in a phase that is not approved, and the building is happening regardless. Buy and price on the roads that exist.

Buying or selling on Phuket’s west coast? Message me on WhatsApp: +66 93 760 8561

Sources: Expressway Authority of Thailand project design (interchanges); The Nation, “Government targets 2031 Phuket expressway Phase 1 opening”, 16 September 2026; The Thaiger and ASEAN NOW reports on the Expressway Authority’s Cabinet timetable, September 2026; earlier target dates as reported in 2021 and October 2025; CV Group announcement of Synthesis Ark Phuket, December 2025. Project sizes and completion dates are developer and government figures. Traffic and drive-time observations are my own.

Rex Butler, Managing Director, Butler Estates. This is general market commentary, not legal, tax or investment advice.