Need to change home currency to USD. All our accounting, sales and purchasing are done in USD. We do have very few MXN transactions.System won't allow me to switch.

Hello, accounts-cabogol. Let me share the details on how to change your home currency in QuickBooks.

You can change your home currency to USD if you haven't activated the Multicurrency feature in QBO. If it's already turned on, take note that QuickBooks doesn't allow you to change the home currency. This is to avoid messing up the account, especially when adjusting the sales tax.

To change the home currency, follow the steps below:

1. Click the Gear icon at the upper right corner. 
2. Select Account and Settings, then choose the Advanced tab. 
3. Go to the Currency section. Then click the pencil icon. 
4. Choose USD from the drop-down arrow. 
5. Hit the Save button, then Done.

If it's turned on, we can either delete the data by purging the file or cancel the account and start over. Here's a link to more information on this: Delete your data and start over in QuickBooks Online.

Learn how to manage home currency adjustments when using the multi-currency feature in QuickBooks Online by reading this article: Frequently Asked Questions about Home Currency Adjustments.

Please keep me updated if you have any additional questions about QuickBooks Online currencies,

@accounts-cabogol 

Another option, open a new QBO account and set USD as the home currency. Then purchase a 3rd party migration service. Contact @Fiat Lux - ASIA for details.