Write-offs are non-cash payments available in the Payments screen. When you choose the payment method Write-off, you are asked what account to apply it to. With accrual-based write-offs, it's usually regarding a bad debt or other expense. However, cash-basis write-offs don’t matter as much because they aren't cash transactions at all; you are writing off something that hasn’t been recognized. Some users create cash-based journal entries for this scenario. Please consult with your accountant to see what other options are available.