Note: If you enable multi-currency, you won't be able to use iOS apps.
Enabling / Disabling Multi-currency
Click on Settings in the top right hand corner.
On the left-hand side click on Business Settings.
Tick the Enable Multi-Currency Support checkbox.
Note: If you don't see this option, you're on a subscription plan that doesn't offer multi-currency. Please change your subscription plan or contact support for help.
Note 2: If you can't change the toggle, it's probably because you don't have Creator/Admin privileges. Read about permissions here.
What happens when multi-currency is disabled?
Once you have enabled multi-currency and have recorded transactions in multiple currencies, disabling the feature doesn't change any of the multi-currency transactions already recorded. What it will do is hide the multi-currency fields, as seen below.
What happens when multi-currency data is imported?
If you import transactions through an add-on like FreshBooks or using the API, and those transactions are not in your home currency, they will be imported as multi-currency transactions, even if the feature is not enabled.