It depends on the type of QuickBooks Online that your accountant is using, FrancesM.
Although creating an account for QuickBooks Online for Accountant is free, accountants will be asked to pay when clients are added to their account. More details about this can be found here: https://quickbooks.intuit.com/uk/accountants/online/.
I'd recommend reaching out directly to your accountant so they can discuss this matter with you.
Visit us again if you have other queries or if you require additional help with QuickBooks.