Formal — to staff
Train · Station
すみません、[目的地]行きの電車は、何番線ですか? — Excuse me, which platform is the train bound for [destination] on? (Train · Station, Formal — to staff, JLPT N4)
You
すみません、[目的地]行きの電車は、何番線ですか?
すみません、[もくてきち]いきのでんしゃは、なんばんせんですか?
Excuse me, which platform is the train bound for [destination] on?
Romaji: Sumimasen, [mokutekichi]-iki no densha wa, nan-bansen desu ka? / Reply Romaji: [Suuji]-bansen desu.
Reply
[数字]番線です。
[すうじ]ばんせんです。
It's platform [number].
Gesture & etiquette
Point at a map, ticket, or hold up a phone with the destination.
Always confirm the train type (e.g., local, rapid, express) and final destination, as multiple lines may share platforms or different trains stop at different stations.