If you’ve lost your receipt, here is a sample template you can use to write an acknowledgment letter for a lost receipt.
To [Recipient name]
Dear, [Recipient name]
This letter is to certify that I have lost the original receipt numbered [Reciept number] and is thereby unobtainable. The receipt was received on [Date] which was for a total amount of [Amount] inclusive of taxes. The receipt accounted for [List of goods or services] by [Vendor name].
I hereby declare that the information provided above is accurate and complete. The receipt was lost due to [State reasons] and cannot be produced at the current time.