Change Grammarly language to UK English
Browser
For your browsers, which affects things like Salesforce, Teams and Outlook on the web, etc. navigate to the Extensions section of your chosen browser. The symbol will look like a puzzle piece:
Chrome:
Edge:
Click on the Grammarly Extension and then click All Settings - this will take you to your account page.
Once on your account page, click Customize on the left and then Language from the tabs presented then under the Dialect section, choose British English.
Note: This changes it for all browsers so you only need to do it in one.
Desktop App
For the desktop app, which affects things like Teams, Outlook, etc. search for the app Grammarly in your Windows search.
The app will open in a small window, click Settings
The top option should be to change the language in the I write in: section. Choose British English.