'on settlement of which'


Senior Member
Hi, everybody,

Can you help me with the meaning of the phrase 'on settlement of which' in the following sentence:

We inclose our pro-forma invoice, on settlement of which your order will be despatched without delay.

Does this sentence sound very formal?

Are there other ways (less formal) to express the same meaning?

Thank you in advance :)
  • I think it should be "enclose" rather than "inclose".

    You could say"

    "Your order will be despatched promptly after payment of the enclosed invoice"

    or "...on receipt of payment..."