與美國貿易需要TIN(?) - 國貿工作討論

想請問版上的各位前輩
這是我們公司第一次跟美國做貿易
剛好我們的客戶也是第一次跟國外買東西 ...
於是就有了不少問題

在e-mail客戶這樣跟我說
I assume your company has done business with other companies in the United States. Hopefully your accounting department knows which Internal Revenue Service forms they need to file and provide to our company in order to receive payment.
Do you have any United States tax indentifying numbers for selling products to US businesses?

所以請問我們是要提供什麼東西給他們?
那個TIN真的是必要的嗎?

因為我們公司很小 也沒有其他人知道
只好上來版上請教各位

先叩謝大家!!

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