Thai addresses use a five-digit postcode whose first two digits mark the province, and Bangkok addresses use sub-districts (khwaeng) and districts (khet). Getting the sub-district or postcode wrong is the usual cause of misrouting. Here is the format, a real example, and the errors to catch.
A Thai label is recipient, the street with its number, the sub-district, then the district or city with the postcode, then the country.
Somchai Prasert romanized recipient name12 Sukhumvit Road house number and road (<code>Thanon</code> for road, <code>Soi</code> for lane)Khlong Toei the khwaeng (Bangkok) or tambon (elsewhere)Bangkok 10110 the district or city, then the 5-digit postcodeTHAILAND required for inbound international shipmentsThailand Post's five-digit postcode has province information in its first two digits (10 Bangkok). It pairs with the sub-district and district, which do much of the local routing.
The country-specific rules that generic autocomplete and single-line address fields tend to get wrong.
Thai addresses nest a sub-district (khwaeng in Bangkok, tambon elsewhere) inside a district (khet or amphoe). Both are needed, since a road can cross several sub-districts.
The postcode's first two digits map to the province (10 Bangkok, 50 Chiang Mai). A transposition routes to a different province.
Many addresses sit on a numbered lane (Soi) off a main road (Thanon). The soi should be kept, since it narrows the location within a long road.
Thai place names have several romanizations. Keep one spelling per address, and ideally provide the Thai script for last-mile couriers.
Each of these passes a basic "is this field filled in" check but fails at the carrier, turning into a redelivery, a return, or an address correction fee.
How the major carriers handle Thailand addresses, and what your label needs to satisfy each one.
The national postal operator. Routing is postcode-driven, and the sub-district and district refine delivery, so all three should be present and consistent.
The dominant private parcel carriers for Thai ecommerce. They rely on the sub-district, district, and soi for accurate last-mile delivery.
International carriers for inbound shipments. They require a romanized address with the country line and charge for corrections on incomplete addresses.
Address Guard checks Thailand addresses against carrier and postal databases before the order ships, normalizes the format, and flags the errors that cause failed deliveries. 240+ countries, $0.05 per check.
Part of the Address Guard international address format guide, covering 240+ countries.