Is there a way to allow customers to log into my QB online license and view their transaction history... and at the same time make payments?

It's my pleasure to share with you an insight about letting your customer view their transactions in your QuickBooks account, Iceguy.

In QuickBooks, you have the options for user roles and access permissions. Here are the steps below to acheive it.

To add a new user:

1. Select Settings menu, then select Manage users.
2. Select Add user, then select a user type. 
3. Click Next, then select the access rights for the user. 
4. Select Next, then select the user settings, if applicable. Then, select Next.
5. Enter the user’s name and email address. Then click Save.

Once done, your new users receive an invite to join the company. Ask them to select the link in the email to create a new Intuit Account, or just sign in if they have an existing one.

You can also manage user role or permissions by following the steps below:

1. Select Settings menu.
2. Select Manage users.
3. Find the user you want to edit. Then select Edit in the Action column.

• You can change the User type ▼.
• Select the user settings you want to manage (if applicable).

Concerning making payments, they can pay bills, write and print checks, and view checks reports, or make bills and purchases billable to customers. 

Should you need to let your customer pay you online, visit this article to learn more about this process: Take and process payments in QuickBooks Online.

Get back here and post some more if you have additional concerns. I'll be there right away to guide you again. 

@Iceguy 

Who are these "customers"? Are you helping them to book their QBO account? or are you actually sending them your invoice and you are thinking of letting them check their own bill?

So what I am asking is there a way a customer can access their account transactions to see what their purchases and payments.  For example, if I was a customer and my vendor uses QB online.... could I be given access to that QB online license only to log in and see my transaction history.  Then possibly to pay my balance via that portal?  

QB does not offer such a customer portal. You need a 3rd party app to integrate with QBO. One free invoicing app offer a customer portal feature and your customers can keep track of all their transactions with you. It will notify you when your customers have viewed or paid for an invoice with a real-time status view.

Hello there, @Iceguy. Let me share further insights if it's possible to let a customer access their account transactions to see what their purchases and payments are in QuickBooks Online (QBO).

I agree with @Fiat Lux - ASIA that the portal where customers like you can access account transactions is unavailable in QBO. For the time being, you'll need to be added as a user to your vendor's QBO account with specific roles and permissions, so you can log in and see your transaction history.

Furthermore, you can create and send customer statements to your customers or ask one from your vendor to show a summary of your invoices, payments, credits, and balances. To do this, here's how:

1. Go to Get paid & pay or Sales, then Customers.
2. Select the checkboxes for the customers you want to make statements.
3. In the Batch actions dropdown, select Create statements.
4. In the Statement Type dropdown, select the customer statement type (Balance Forward, Open Item, Transaction Statement).
5. Select the dates for the statements and the date range.
6. Review the customer's email addresses.
7. Select Save, Save and close, Save and send, or Print or Preview.

To know more about the process above, please see this article: Create and send customer statements in QuickBooks Online.

Also, I'm including this article as your reference in accepting electronic customer payments for online invoices and in-person sales in QBO: Take and process payments in QuickBooks Online.

Please don't hesitate to comment below if you have other concerns about managing customer transactions and user permissions in QBO. I'm always ready to help. Take care, and have a great day, @Iceguy.