Cancel through your Microsoft account (Java Edition, and Bedrock Realms started on a PC or Xbox)
- 1
Visit your Microsoft account settings at https://account.microsoft.com/ in a web browser.
- 2
Sign in with the Microsoft account used to purchase your Minecraft Realms subscription.
- 3
Open the Subscriptions section from the menu on the left side of the page.
- 4
Locate the Realm subscription that needs to be cancelled and select Manage.
- 5
Select Cancel subscription.
- 6
Select Cancel subscription from the pop-up window.
Source: help.minecraft.net — the provider's own documentation for these steps.