我公司欠 a 公司運費, 現 a 公司要求我公司將該欠款支付去另一間 b 公司名義的銀戶口 !

曾作為會計部主管的我, 易地而處, 會斷言拒絕有關要求！
縱然, 我承認, 上述兩位網友所答, 都是具可行性的做法, 然而, 卻非最好。原因如下:
1.) 增添會計同事的工作量; 或減低工作效率, 非管理人員所取。
2.) 改變工作(出票)流程, 容易出現錯誤; 更缺乏成本效益。
3.) 公司需具制度化和統一, 不應受外界影響。
4.) 風險管理: 有關的要求, 不能完全排除, 不存在欺詐、隱瞞和不誠實的行為，因此, 若按照不同機構的要求, 自己工作的公司, 無論在營運、形象和誠信上, 無可避免地, 增加不穩定的因素。
基於上述的原因, 我建議拒絕有關要求。

In general, it is an accepted settlement of debts. But, you have to get an instruction and an acknowlegment for such settlement in written form. In strict term, this kind of arrangement must be with the consent of all parties – your company, A and B.
However, as you could not know the dealing behind the payment by you to B instead of A, it is better that the payment be made direct to A. A could then issue a cheque direct to B immediately. If there is a dispute between A and B involving this arrangement for payment of debt by your company, you will be getting into an undue involvement.

當然有問題, A公司可以抵賴話無收過錢
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