Dear :

Your name was given to us by [name], [position] of [company], who has asked us to allow them to settle their account by -day draft. They told us that you would be willing to act as their referee.

We would appreciate it if you could confirm that [company] settle their account on due dates and are able to meet credits up to $ in transactions.

Thank you for your help.

Sincerely yours,

[name]

[title]