1. 文體介紹
催收信是賣放在規定期限內未收到貨款，提醒或催促買方付款的`函件。
寫此類信要求文字簡練、意思清楚；同時要求語氣誠懇、體貼，彬彬有理。不可輕易懷疑對方故意拖欠不付，以免傷害對方感情，不利於達到索款的目的，或妨礙以後的業務。對於某些屢催不付，故意逃款的客戶，語氣則要強硬，措辭堅決。
總之索款要把握一個原則：既要達到索款目的，又要與客戶保持友好關係。
2。實用範例
1subject: Demanding Overdue Payment
Dear Sirs,
Account No.8756
As you are usually very prompt in settling your accounts, we wonder whether there is any special reason why we have not received payment of the above account, already a month overdue.
We think you may not have received the statement of account we sent you on 30th August showing the balance of US$ 80,000 you owe. We send you a copy and hope it may have your early attention.
Yours faithfully,
xxx