Thailand for October Half Term: The Week the Monsoon Flips

If your week is the late-October half term, the honest answer is that you have landed on the exact fortnight Thailand’s weather changes its mind — and the coast you pick matters far more than the dates you cannot move. Broadly: the Andaman side, Phuket and Krabi, is drying out through late October and improving week by week. The Gulf islands, Samui and Phangan, are heading the other way into their own wet season. A week that is good on one coast can be genuinely poor on the other.

Half term against the Thai calendar

UK half term falls at the end of October and drifts by up to a week depending on the local authority and school, which is why two families can have very different trips from the same “October half term”. That drift is not a rounding error here. Thailand’s southwest monsoon eases through October rather than stopping on a date, so a week starting the 19th and a week starting the 26th are not the same week — the later one is usually better on the west coast.

The flip, in one paragraph

Two monsoons run the southern peninsula. The southwest monsoon soaks the Andaman coast from around May to October, and September is typically its worst month. The northeast monsoon then takes over on the Gulf side from around October into December, with November often the wettest month on Koh Samui. Late October sits in the handover: one coast is coming out, the other is going in.

Why Phuket and Krabi are the safer bet

By the last week of October the west coast is usually past the worst of it. You should still expect rain — this is the tail of a monsoon, not the middle of the dry season — but it is more likely to arrive as a heavy afternoon hour than as a lost day. Beaches that were red-flagged in August are calming down, and the day-trip boats to Phi Phi and the Krabi islands are running more consistently, though the decision is still made on the morning.

The Samui trap

The single most common booking mistake for this week is picking Koh Samui because “Thailand is dry from November”. On the Gulf coast that is close to the opposite of true. November is often Samui’s wettest month, and late October is when it starts. A half term that runs into the first days of November is edging into the worst of it. Samui in that window is not impossible, but it is the higher-risk choice, and it should be a deliberate one.

Where	Late October	Early November
Phuket, Krabi, Khao Lak	Improving, showers likely	Usually good, high season starting
Koh Samui, Koh Phangan	Turning wetter	Often the wettest of the year
Bangkok	Rains easing, still humid	Cooler and drier
Chiang Mai and the north	Green, drying, cooler nights	Dry season, cool mornings

Bangkok and the north in that fortnight

If the beach is the risk, the north is the hedge. Chiang Mai and the hills around it come out of the rains earlier than the coasts, and late October into November is when the mornings turn cool and clear. For a family week with a long flight at each end, splitting between Bangkok and Chiang Mai avoids the boat cancellations entirely and keeps travel times short.

The clock change nobody plans for

Thailand is UTC+7 all year and does not use daylight saving. The UK does, and the clocks go back on the last Sunday of October — right in the middle of the half-term window. So the time difference is six hours before that Sunday and seven hours after it. If your flight, transfer or a booked activity sits either side of the change, check the local times rather than doing the arithmetic in your head, because a booking made in one gap and used in the other is exactly how a family misses a pickup.

Loy Krathong, if the dates fall right

Loy Krathong is set by the lunar calendar and usually lands in November, occasionally brushing the end of October. In the years it falls inside a late half term, it is the best evening of the trip — but the date moves annually, so confirm the year you are travelling against an official Thai tourism calendar rather than assuming last year’s date repeats.

What to book and what to leave loose

Book the flights, the airport transfer and the first two nights. Leave one internal leg flexible if you can, because with fixed dates the only variable you control is location. Domestic flights between Bangkok, Phuket, Krabi and Chiang Mai are frequent enough that changing plan mid-week is realistic rather than theoretical. If you want the fuller coast-by-coast picture across the rest of the year, our rainy season guide covers every month, and the overland route to Koh Samui is worth reading before committing to the Gulf in this window.

Arriving with a working phone

A week this short does not have an afternoon to spare on a SIM queue, and with fixed dates the ability to rebook from the airport is worth more than usual. A data plan installed at home means the family lands connected, can order a car, and can message a hotel about a delayed transfer without hunting for airport Wi-Fi — our Bangkok arrival guide walks through that first hour, and you can compare data allowances on the pricing page before you fly.