不客气。

Using it is incredibly simple. Whenever you hear 谢谢, you can fire back with 不客气. It works just like 'you're welcome' in English. You can say it quickly while walking past someone. You can also say it slowly with a smile to show you really mean it. If you want to sound even more polite, you can add 太 to make it 太客气了. But for 90% of your daily life, the three-syllable 不客气 is your best friend.

Use this in almost any standard social situation. It is perfect when you hold a door open for a stranger. It works great at a restaurant when the waiter thanks you for your order. Use it with colleagues when you help them with a small task. It is the 'goldilocks' of phrases—not too stiff, not too casual. It fits right in the middle of everyday life. Even if you are texting, it is a safe and clear choice.

Don't use this with your absolute best friends or very close family. In China, being 'polite' to your inner circle can actually feel cold. It implies there is a distance between you. If your best friend thanks you for a snack, 不客气 might sound like you are keeping them at arm's length. Also, avoid using it with your boss in a very high-stakes formal meeting. In those cases, you might want something more humble. If you are feeling lazy, don't just grunt it; give it some tone!

Chinese culture places a huge emphasis on the concept of 'guest' behavior. Being 客气 is usually a good thing, but between friends, it is unnecessary. The phrase reflects a culture that values closeness and 'family' feelings over formal etiquette. By saying 不客气, you are inviting the person into your circle. You are telling them that favors are just what people do for each other. It is a verbal way of lowering the walls between two people.

You will often hear 不用谢, which means 'no need to thank.' This is very common in Northern China and feels a bit more casual. Another one is 没事, which means 'it's nothing' or 'no problem.' If you are in Taiwan, you might hear 不客气 said with a softer tone. In very formal settings, people might say 您太客气了. For the younger crowd, just a simple 'OK' or a nod sometimes replaces the phrase entirely. But stick with the original until you feel like a pro!