彼らは小さな町に住んでいます。

English Translation

They live in a small town.

Is the pronunciation of 町 interchangeable here between まち and ちょう?

@TisYanni
No. まち is the only correct pronunciation in this sentence. ちょう cannot be preceded by adjectives. ちょう is used only as a part of toponyms (unique nouns) or as compound words.

For example,

  • 石川県志賀町 (いしかわけん しかまち): The Shika Nuclear Power Plant is located in this town and was hit by a tsunami after the 2024 Noto Peninsula Earthquake

  • 石川県能登町 (いしかわけん のとちょう): Another town hit by the 2024 Noto Earthquake

  • 全国の市町村 (ぜんこくの しちょうそん): meaning “cities, towns and villages across the country”

  • この町内に公園はありません (ちょうない): meaning “there is no park in this town.”

まち and ちょう in these examples are not interchangeable.

There is no rule when a town name is pronounced 〜まち or 〜ちょう. 市町村 is a technical compound word frequently used in the context of municipality administration.