MacOS Spell Check with British Keyboard: USE English Instead

To use American English spell checking while keeping a British keyboard layout on macOS, you must add the US English input source in System Settings without changing your primary system language. This ensures that date and currency formats remain British while text correction follows American rules.

Distinguishing Input Sources from System Languages

A common misconception is that changing the primary language in your region settings will switch your spell checker to American English. This is factually incorrect. Changing the primary language alters fundamental system behaviors, including date formats (DD/MM/YYYY vs MM/DD/YYYY), currency symbols, and time zones. To isolate spell checking behavior, you need to modify only the input sources, which control how characters are entered and validated by the text engine. The macOS text correction system operates independently of the regional format settings. By adding a second keyboard layout or language input method, you can toggle between them using a shortcut. The spell checker automatically adapts to the currently active input source. Therefore, the goal is to keep British English as your main system locale for regional consistency while enabling American English as an available input source for typing and proofing.

Accessing Keyboard Settings

Navigate to the system configuration area by clicking the Apple menu in the top-left corner of your screen. Select System Settings (or System Preferences on older versions). In the sidebar, locate and click on Keyboard. This section manages all input-related configurations, including physical layouts and software input methods. If you are using a version of macOS where keyboard settings are nested differently, look for Language & Region first, then select Text Input or Input Sources. The exact label may vary slightly depending on your macOS version, but the functionality remains consistent across modern releases.

Adding the US English Input Source

Once inside the Keyboard settings, find the section labeled Input Sources or Keyboards. Click the + button to add a new source. You will see a list of available languages and layouts. Search for or scroll to English (US). Select English (US) from the list. Ensure that the specific variant selected is either ABC or U.S. depending on your preference for standard QWERTY layouts. Avoid selecting variants like British or Canadian French if you specifically want American spelling rules. Click Add to confirm the selection. You should now see both English (UK) and English (US) listed in your input sources. The order does not strictly matter for functionality, but having both listed confirms that the system recognizes both locales for text entry.

Toggling Between Keyboards

To switch your spell checker to American English, you need to activate the US input source. There are several ways to do this efficiently. The most common method is using the keyboard shortcut. By default, macOS allows you to cycle through input sources using Control + Space or Fn (Globe) key, depending on your configuration. You can also enable a menu bar icon for easy switching. In the Input Sources settings, check the box that says Show Input Menu in Menu Bar. This adds a small flag or globe icon to your top right status bar. Clicking this icon displays a dropdown list of your configured input sources. Select English (US) from this list. When you type in any application, such as TextEdit, Safari, or Microsoft Word, the spell checker will now underline errors based on American English dictionaries. Words like colour or recognise will be flagged as misspelled because they do not match the US dictionary. Conversely, color and recognize will be accepted.

Verifying the Change

Open any text editor and type a word with a distinct spelling difference, such as neighbour (UK) versus neighbor (US). If the US input source is active, neighbour will likely show a red squiggly line under it. Type neighbor; it should appear clean. This confirms that the spell checker is correctly aligned with the US input source. If you wish to return to British English spelling, simply click the input menu icon again and select English (UK). The spell checker will immediately revert to British rules. This toggle happens instantly without restarting applications or reloading the system.

Common Issues and Troubleshooting

Sometimes, applications may cache the previous spell-checking language. If you switch input sources but still see British spell-checking results, try restarting the application. Most modern apps respect the current input source state, but some legacy tools might require a fresh launch to pick up the change. Ensure that you have not inadvertently changed the primary language in Language & Region. Your primary language should remain English (UK) to preserve British dates and currencies. Only the secondary input source should be set to English (US). For users who frequently switch between locales, consider customizing your keyboard shortcut. Go back to the Keyboard settings and select Shortcuts. Under Mission Control or Input Sources, you can assign a more memorable key combination to switch between UK and US inputs. This reduces friction when writing documents that require mixed localization standards.

Frequently Asked Questions

Will changing the input source affect my system language?

No, adding an input source does not change your system language. Your system language controls menus, dates, and currencies, while input sources only affect text entry and spell checking. You can keep British English as your system language while using American English for typing.

How do I know which input source is currently active?

Look at the menu bar in the top-right corner of your screen. If you enabled the input menu, you will see a flag or globe icon. The current icon indicates the active language. Alternatively, press Control + Space to cycle through sources and observe the visual change.

Why does spell check still show British errors after switching?

Some applications cache their language settings. Restart the application after switching the input source. Additionally, ensure you are editing in a field that supports rich text and spell checking, such as Pages or Safari, rather than plain text fields that may lack dictionary support.

Can I use different spell checkers for different apps?

macOS generally applies the spell checker based on the active input source globally. However, third-party applications like Microsoft Office may have their own independent language settings. Check the app’s preferences if it ignores the system input source.

What if I want Canadian English instead of US English?

The process is identical. Add English (Canada) as an input source in the same menu. Canadian English shares many similarities with US spelling but retains some British conventions. Select it from the input menu just like you would for US English.