How to write off an insurance adjustment?

Hello, nani00. 

Entering and recording transactions will always affect your books. That includes writing off an insurance adjustment for the invoice. That said, I do have the steps to help you record the write off. 

You can write off the insurance adjustment by creating a credit memo, then applying it to the invoice. Here's how: 

1. Go to the Customers menu, then select Create Credit Memos/Refunds.
2. Select the customer (the insurance company) under CUSTOMER:JOB. 
3. Under the item table, select the services rendered. 
4. Under the Memo field, enter something like "Insurance pay off" or something similar. 
5. Click Save & Close.
6. Select either Retain as available credit (if you don't have an invoice yet) or Apply to an invoice (if you already recorded it). 
7. Click OK.

The credit will be applied automatically if you select Apply to an invoice. However if you retain it as an available credit, you'll want to manually apply it. Here's how: 

1. Open the invoice (for $5000).
2. Click the Receive payments button.
3. Check the invoice.
4. Under the UNUSED CREDITS section, click Apply Credits. 
5. Check the credit memo, then hit Done.

An amount of $1000 will be deducted from $4000 after applying the payment and the credit memo. 

If you're ready to categorize your Online Banking transactions, you can check this article for the steps: Add and match Bank Feed transactions in QuickBooks Desktop.

Do you need to reconcile your payments instead? This article can definitely walk you through the process: Reconcile an account in QuickBooks Desktop.

I'm willing to help out again if you have more concerns about managing your invoices. Do you have any other questions? Ask away and I'll address them.