Where is the Quickbooks Menu option for me to add a bank signature for checks?

Welcome to the Community, swfoundation-swm.
 

If you're using your QuickBooks mobile app, you can capture signatures from customers for estimates or invoices.
 

Here's how to capture a signature on iOS devices:
 

1. Go to Menu (☰), then Estimates or Invoices.
2. Choose an existing transaction, or create a new one.
3. Add any necessary details and tap Save.
4. Hit Get Signature, then have the customer sign with their finger.
5. Select Done.

For Android devices, your steps will be a bit different. You can refer to our Capture signatures article for detailed steps.
 

In regard to bank signatures for checks, I can certainly understand how such an ability could be useful and have submitted a suggestion about it as of today.
 

You can also submit your own feature requests while signed in.
 

Here's how:

1. Use the Gear icon, then go to Feedback.
2. Enter your suggestion(s) in the Have feedback? window.
3. If necessary, attach a file with your Camera icon.
4. Select Next.
   
   

Your feedback's definitely valuable to Intuit. It will be reviewed by our Product Development team and considered in future updates. You can stay up-to-date with the latest news about your product by reviewing Intuit's Product Updates webpage.
 

You can also check our QuickBooks App Store for apps which may be able to help you achieve what you're looking to accomplish.
 

I'll be here to help if there's any questions. Have a lovely Tuesday!