If you return this form to the sender, service of a summons is deemed complete on the day you sign the acknowledgment of receipt below. (A sample Claim Form is attached as Attachment 2.) b.Format a Payment Acknowledgement Letter Instantly with a Sample in DOC, PDF, and More. Up through this point in our series, we've been using the hypothetical Smith couple as the example to complete each form. The sample acknowledgement letters for receipt of payment provided below can be used as format templates for official and personal purposes.