I need to change my user id, because the company email is going to change. How do I change my account to another user id already created?

I'm happy to walk you through changing your QuickBooks user ID, @mromero. 

First off, sign in to your QuickBooks Online account as the master admin to update your info in the account manager. Then, follow the steps below:

1. Go to your profile icon next to Settings.
2. Select Manage your Intuit Account to open the Intuit Account Manager.
3. Click the Sign in & security menu.
4. Select the User ID and make some changes.
5. Click Save.

Here’s an article where you can read FAQs about resetting your password and signing in: Change your email, user ID, or password for QuickBooks Online.

You also want to use one email and user ID for all of your QuickBooks Online companies or change specific areas, see these articles for your references to guide you through the process:

• Sign in to multiple QuickBooks Online companies with one user ID
• Change your business name, contact info, or Business ID No in QuickBooks Online

You can always count on me should you need more assistance in managing your QuickBooks account. Take care!