失陪(shī péi) - excuse me, I must be going in Mandarin

失陪 (shī péi) is the formula for leaving company politely. You say it as you get up from a table, step out of a meeting or end a conversation, and it apologises for the leaving rather than for anything you have done.

It usually comes with a softener: 失陪一下 for a short absence you will return from, 我先失陪 for going ahead of the others, 我失陪了 for leaving properly. On its own it is fine but abrupt.

The trap is register. This is a courteous, slightly formal expression, so it fits a business dinner or a host you barely know, and sounds theatrical among close friends, who would simply say 我先走了. Do not use it as a general sorry either: it only ever means I am leaving your company, never I apologise.