How do I download missing banking and credit card activity for 2018?

You've come to the right place, w-2-w.

I have just the steps that'll help download the missing bank and credit card transactions.

The first time you connect your bank or credit card account to QuickBooks will download the last 90 days of transactions. If you need more than that, you can export additional historical transactions from the financial institution's website and upload them into your QuickBooks. The steps below will guide you through the process:

To download transactions from your bank's website

1. Log into your financial institution's website.
2. Follow their process to download your transactions to your computer.
3. Choose a supported file type for the download file. Make sure to select the .QBO file format.
4. Take note of the name of the file you downloaded, and the location you downloaded it to so you can easily find it to upload.

To upload the file to QuickBooks

1. Click Banking in the left navigation menu.
2. From the Update drop-down menu, select File upload.
3. Click Browse and choose the file you downloaded from your bank.
4. Hit Next.
5. From the QuickBooks account drop-down list, select the account to which to upload the bank transactions, and click Next.
6. Click Let's go! (or Finish, depends on what you see).

For future reference, I'm also including our guide on how to upload more than 90 days of bank transactions.

That should get you going in the right direction. Don't hesitate to keep in touch if you need more help with your missing transactions. I always have your back and am always happy to help. Have a great day!