A Comparison of the Thai and Lao Languages

Thailand and Lao are Southeast Asian countries that share a long border, much of it marked by the mighty Mekong River. Culturally, they’re very similar, with Theravada Buddhism as their primary religion, and both peoples consider the other to be close cousins.

However, their recent histories are very different; Lao was part of French Indochina, while Thailand was never colonized by a Western country.

Also, during the Vietnam War, the Ho Chi Minh Trail that sent supplies from north to south Vietnam passed through Lao, leading to a bombing campaign from U.S. forces that resulted in Lao becoming the most bombed country per capita in history.

The effects of this undeclared war are still felt today, with people being killed or maimed every year by leftover bombs, particularly in the south of the country.

The Thai and Lao languages belong to the Kra-Dai language family, and native speakers of one can generally understand the other. Native Lao speakers often have better spoken Thai than vice versa, as Thai television is popular in Lao.

For language learners, though, it’s very different. Regional accents and dialects in both countries are enough to confuse all but the most advanced learner, let alone trying to understand a different language with a different script.

In this article, we outline some similarities and differences between Thai and Lao, explain how they came about, and highlight some difficulties Westerners face when learning these languages.


Approximately 80% of words in the Thai and Lao vocabularies are cognates, meaning they originate from the same parent language.

Languages are forever changing, so cognates may not be immediately apparent, but some that are obvious in Thai and Lao are listed in the table below.

Table: Examples of vocabulary words which are similar in Thai and Lao
Thai Lao English
ภาษา (phāsā) ພາສາ (phāsā) language
วัน (wan) ວັນ (wan) day
ข้าวเช้า (kâao-cháao) ເຂົ້າເຊົ້າ (khao sao) breakfast
ผัก (phak) ຜັກ (phak) vegetable
ห้อง (hɔ̂ng) ຫ້ອງ (hong) room
เตียง (teīyng) ຕຽງ (tīang) bed
ยินดี (yindī) ຍິນດີ (nyindī) happy
อ่าน (àan) ອ່ານ (ān) to read
เข้าใจ (kâo-jai) ເຂົ້າໃຈ (khao chai) to understand
เพลง (pleeng) ເພງ (phēng) song
ประตู (pratū) ປະຕູ (pa tū) door
คืน (khụ̄n) ຄືນ (khūn) night
ได้ยิน (dâiyin) ໄດ້ຍິນ (dainyin) to hear
ป่า (bpàa) ປ່າ (pā) forest
พ่อ (pɔ̂ɔ) ພໍ່ (phǭ) father
สุด (sùt) ສຸດ (sut) to end
ต้นไม้ (dtôn-máai) ຕົ້ນໄມ້ (tonmai) tree
เลือก (leụ̄xk) ເລືອກ (lư̄ak) to choose
รัก (rák) ຮັກ (hak) to love
ขอบใจ (kɔ̀ɔp-jai) ຂອບໃຈ (khǭp chai) to thank
เห็น (hěn) ເຫັນ (hen) to see
เล่า (lèā) ເລົ່າ (leoa) to tell
ไป (bpai) ໄປ (pai) to go
เปิด (peid) ເປີດ (poed) to open
ชนะ (chá-ná) ຊະນະ (sana) to win
ชายแดน (chāydæn) ຊາຍແດນ (sāi dǣn) border

Rather conveniently, numbers in Thai and Lao are the same, and asking “how much” is very similar, so at least you can shop in both countries with just one of the languages!

The Thai and Lao scripts

To the untrained eye, both scripts look almost the same at first glance. But on closer inspection, you’ll notice that Thai script is quite angular, whereas Lao is more curved and flowing.

Thai script has 44 consonant symbols, 16 vowel symbols, and four tone marks. In contrast, the Lao script has 27 consonant symbols, 33 vowels, and four tone marks. Both scripts were derived from the Khmer script of Cambodia.

In general, consonants give a syllable a high or low tone, and vowels are either long or short. And this is where it gets complicated! Vowels are often comprised of more than one symbol and can be placed before, after, or above a consonant.

Sometimes, a single vowel sound can consist of three symbols wrapped around a consonant, making it even harder to learn how to read. Tone marks are usually found above a syllable but are occasionally placed underneath.

There’s no denying that both scripts are fiendishly difficult to learn, made even more so by the fact that neither uses spaces between words, some consonants can be used for vowel sounds, and there are silent consonants, some of which change the tone of the syllable.

However, neither is as difficult as the Chinese writing system, and as you progress, what initially seemed impossible becomes easier. Devoting the time to learning the script will certainly allow you to become more proficient in either language than learning the spoken form alone.

Why does Thai have more consonants than Lao?

The Thai script contains several consonants representing the same sounds, as ancient Thai contained numerous loanwords from Sanskrit and Pali. Over time, spoken Thai has evolved, and these loanwords have disappeared from the language, leaving duplicate consonants to show where the word originated.

In contrast, the Lao script was simplified and brought closer to the spoken form, removing the duplicate consonants.

Other similarities

Indic loanwords

Many Southeast Asian languages are influenced by one of the two regional cultural powerhouses: India and China. Both Thai and Lao contain loanwords from the ancient Indian languages Sanskrit and Pali. (see this comparison of Thai and Sanskrit)

The Pali language (which originates from Sanskrit) is the language of the Pali Canon, the sacred text of Theravada Buddhism, the primary religion in both countries. So it’s unsurprising that both languages contain Pali loanwords.

Changing pronouns

Like many languages, both Thai and Lao have levels of formality. Both change pronouns according to the level of formality the situation requires and the relative social standing between speakers.

This can seem confusing to learners, especially as it can be difficult for Westerners to determine what “social standing” actually means in Asia. However, it’s not as tricky in Lao or Thai as in a language like Russian, where pronouns, verbs, adjectives, and adverbs all change with formality, and it’s likely you’ll only need the informal form.

Native speakers of Asian languages rarely expect a Westerner to understand the nuance of their language, so you’ll be unlikely to offend by using informal pronouns.

Verb tenses

Unlike English, verbs in Thai and Lao don’t change with tense or subject pronouns. So there’s no need to worry about subject/verb agreement (she has/they have, for example), and a time clause and additional word signify tense.

English is similar in future tense, requiring “will” or “going to” to show something in the future. Both Thai and Lao do the same for past and future tense. For example, “will” is ຊິ (sī) in Lao and จะ (jà) in Thai.


Both Thai and Lao are tonal languages, an aspect of many Asian languages that Westerners sometimes obsess over. Tones are important, but they’re a part of the language you quickly become accustomed to.

Don’t think about them too much, just mimic native speakers you hear face-to-face or online, and you’ll soon add them without realizing it.

Thai has five tones (high, mid, low, falling, and rising), whereas Lao has six, as high falling and low falling are separate tones.


Thai and Lao both use particles at the ends of sentences to convey additional meaning or emotion.

Particles added for politeness in Thai include ครับ (kráp), used by male speakers, and ค่ะ (kâ), used by female speakers.

The particle ແດ່ (daae) is added at the end of a sentence in Lao to indicate you’re making a polite request.

The Isan language

The Isan region of northeastern Thailand was culturally and politically part of what is present-day Lao until the French—Thai war that ended in 1893. The local language is a descendant of the Lao language, and the name Isan comes from the Sanskrit word ईशान्य (īśānya), meaning “northeast.”


Like nearly all Asian languages (with the possible exception of Indonesian/Malaysian), Thai and Lao are challenging for Westerners to learn. However, Thailand is an extremely popular destination for digital nomads and Western retirees, and Lao may try to emulate Thailand in this regard.

If you’re considering spending time in either country, learning at least some of the language makes your stay much easier and allows you to access and understand more of the local culture and history.

Moreover, the people in both countries sincerely appreciate Westerners who try to speak their language and will likely help you as much as they can, even if that means filling your head with dozens of new words in every conversation!