Utilities on Koh Phangan: water, electricity, internet and road access

Utilities on Koh Phangan are not a given. Government mains water covers the main developed areas but the island has a chronic supply shortfall. Power is improving with a major submarine cable upgrade underway, but outages during peak season remain a known reality. Internet is workable in populated areas via 4G but limited compared to the mainland. And road access — which affects every other utility — ranges from the sealed ring road to steep unpaved tracks that become impassable in monsoon. Understanding a specific plot's utility situation is part of due diligence, not an afterthought.

Water: the most variable utility

Koh Phangan has a structural water shortage. The Royal Irrigation Department has established that annual water demand on the island is approximately 600,000 cubic metres — roughly double the available supply. Drought conditions have been officially declared during dry periods, with tap water rationed on parts of the island. Provincial waterworks mains coverage is concentrated in Thong Sala and the larger developed communities; coverage thins rapidly on hillside and remote plots.

• Government main (Provincial Waterworks Authority) — available in Thong Sala and the main established communities. Pressure and reliability can vary seasonally; supply cuts are possible in the dry season (November–April). Verify that the specific property has a registered meter and live account, not merely that a main passes nearby.
• Private well or borehole — common on land plots away from main roads and on hillside properties. The island's granite and sandstone geology can hold groundwater, but yield and quality vary significantly by location. Have any existing well tested for yield and potability before relying on it as the primary supply.
• Rainwater collection tanks — roof-catchment systems supplement or replace mains supply on some properties. Practical in the wet season (May–October); in the dry season a stored-water arrangement is needed.
• Tanker delivery — plots without a well or mains connection receive water by truck. It functions, but it is a running cost and a supply dependency that should be confirmed and factored into holding costs before purchase.

The Royal Irrigation Department is in the Environmental Impact Assessment stage of a 400 million baht subsurface dam project — the first of its kind in Thailand, based on Japan's Miyako Island model — designed to increase groundwater storage and address the structural deficit. Until this project is built, every non-mains plot should be assumed to require a verified alternative supply.

Electricity: PEA connection and the upgrade underway

Power is supplied by the Provincial Electricity Authority (PEA). The island currently receives electricity through four ageing submarine cable circuits — two at 115 kV and two at 33 kV — with a total design capacity of approximately 174 MW. Partial faults and capacity shortfalls during peak tourist season (November–April) are a known feature of island electricity supply.

A major upgrade is under construction. In February 2023, the Cabinet approved an EGAT project to install two 230 kV submarine cable circuits from Khanom Substation on the mainland to a new substation on Koh Samui — 50 km in total — adding 400 MW of transmission capacity (200 MW per circuit) to the wider island group that includes Koh Phangan and Koh Tao. When complete, this substantially upgrades grid stability and available capacity for all three islands.

• In developed areas and near main roads — a PEA meter connection is standard. Verify that the meter is registered to the specific property (not a shared meter with a landlord), and note whether the supply is single-phase or three-phase — relevant if you plan a pool pump or high-load equipment.
• On remote or hillside plots — electricity may require a transformer extension at additional cost and with a lead time. Request evidence of an active, registered PEA meter at the plot address, not just assurance that 'electricity is nearby.'
• Solar — increasingly used on new villas as a supplement or primary supply. Grid-tied systems require PEA approval; off-grid solar with battery storage is a practical alternative for remote plots where grid connection is delayed or expensive.

Internet and mobile connectivity

Internet access in Koh Phangan's main communities is workable for most remote workers, but is substantially behind mainland Thailand in speed and reliability. Following the 2023 merger of DTAC and TrueMove H, the two providers are now AIS and True Corporation.

• 4G mobile data — the primary internet for most island residents. AIS has marginally better island coverage than True. Coverage is reliable in Thong Sala, Sri Thanu, Haad Rin and the main western-coast communities. Interior and remote plots have patchy signal; physically check the signal at the specific plot with your intended SIM before buying to build.
• Fixed broadband — available in parts of the main developed areas, but speeds and consistency are well below the 200–1,000 Mbps fibre standard available in Bangkok and major Thai cities. Plan around 4G as the primary connection, with fixed broadband as a backup where available.
• Congestion — Full Moon Party nights in Haad Rin bring 10,000–30,000 people to a small area and severely overload both networks. Island-wide, all connections face higher loads in high season (November–April). Plan production-critical work around off-peak hours.
• Coworking — venues such as BeacHub in Sri Thanu provide business-grade internet connections for members, effectively bypassing residential connectivity limitations for office hours.

Road access: the utility that determines all the others

A plot with power, water and internet but no legally confirmed road access is effectively unusable. Road quality on Koh Phangan ranges from the sealed main ring road to steep concrete hillside paths to unpaved jungle tracks that become impassable in the wet season.

• Main ring road — the sealed perimeter road is well-maintained and year-round passable. Properties directly on or close to it have reliable access.
• Concrete secondary roads — most established communities have concrete roads, generally usable in all seasons but subject to cracking, level drops and steep gradients on hillside approaches.
• Unpaved tracks — particularly to remote hillside and interior plots. Passable in the dry season; some become mud channels in the wet season. Verify the condition in person during or after heavy rain, not only on a dry-day visit.
• Registered right of way — the critical legal point. A visible track, a verbal agreement or a gentleman's understanding is not a protected legal right. The road access to the public road must be registered on the title deed as a servitude; without it, a new owner of any connecting plot can block access. See Due diligence before buying on Koh Phangan.

What to verify before you commit

Each utility must be confirmed against documentary evidence — not a seller's assurance.

• Water — request the Provincial Waterworks account number and meter reference for the property, or a well-yield and quality test report, or the written supply arrangement if water comes from a shared tank or delivery service.
• Electricity — request the PEA account number and meter serial number registered to the plot address. Confirm supply phase (single-phase or three-phase) if relevant to your planned use.
• Internet — test 4G signal at the specific plot with the SIM of your preferred provider. For an existing building, check whether fibre or ADSL termination is physically present at the address.
• Road — walk the complete route from the public road to the plot. Have your lawyer confirm a registered right of way on the title deed — not merely a track you can see.

Utilities are not glamorous, but they are what makes a plot liveable and determine running costs for the life of ownership. A plot with government mains water, a registered PEA meter and sealed concrete road access is a meaningfully different asset from one that relies on tanker delivery, a distant transformer and an unregistered track.