New Outlook Spell Check Language Override Per Email: How to Set

When composing an email in the new Outlook for Windows, you may need to write parts of the message in a language different from your default proofing language. The new Outlook includes a per-email spell check language override feature that lets you set a different dictionary for the entire message without changing your global Office language settings. This article explains how to activate and use the language override for a single email, what prerequisites are required, and what limitations apply.

How the Per-Email Spell Check Language Override Works in New Outlook

The new Outlook for Windows uses the proofing language installed on your system through Microsoft 365 or Windows language packs. By default, the spell checker applies the language set in Outlook options or the default Windows display language. The per-email override feature allows you to select a different proofing language for a single email message without affecting other messages or your global settings. This is useful when you correspond with recipients who use a different language or when you need to include foreign terms that the default dictionary flags as errors.

The override works by changing the language tag applied to the entire email body. Once you set the language, the spell checker uses the corresponding dictionary for real-time underlining and the manual spelling check. The language override persists only for that specific message. When you close the compose window or send the email, the proofing language reverts to your default setting for the next new message.

Prerequisites for Using the Language Override

Before you can set a per-email language override, ensure the following conditions are met:

• You are using the new Outlook for Windows. The classic Outlook does not support this per-message override in the same way.
• The target proofing language is installed on your computer. You can add a language pack through Windows Settings > Time & Language > Language & Region or through Microsoft 365 language accessories.
• Spell check is enabled in Outlook. Go to File > Options > Mail > Spelling and Autocorrect and verify that Check spelling as you type is turned on.

Steps to Set the Spell Check Language Override for a Single Email

Follow these steps to change the proofing language for the current email message only.

1. Open a new email message
   In the new Outlook, click New Mail or reply to an existing message to open the compose window.
2. Go to the Review tab
   In the ribbon at the top of the compose window, click the Review tab. This tab contains the Language group.
3. Click Language and select Set Proofing Language
   In the Language group, click the Language button. From the dropdown menu, choose Set Proofing Language. A dialog box opens showing all installed proofing languages.
4. Choose the desired language
   In the Language dialog box, select the language you want to use for spell checking this email. For example, select French (France) if you are writing a message in French.
5. Click OK
   Click OK to apply the language override. The spell checker now uses the selected dictionary for this message only. Red underlines for words in the new language should disappear if they are correctly spelled in that language.

To verify that the override is active, type a word that is correctly spelled in the selected language but would be flagged as an error in the default language. The word should not show a red underline.

Alternative Method: Using the Language Bar or Keyboard Shortcut

If you have multiple input languages configured in Windows, you can also switch the proofing language using the language bar or a keyboard shortcut.

1. Enable the language bar in Windows
   Go to Windows Settings > Time & Language > Typing > Advanced keyboard settings. Under Switching input methods, select Use the desktop language bar when available. The language bar appears on the taskbar or desktop.
2. Switch the input language while composing
   Click the language bar icon and select the target language. Alternatively, press Ctrl+Shift to cycle through installed input languages. The proofing language in Outlook follows the active input language.

Note that this method changes the input language globally for all applications, not just the current email. To revert, switch back to your default input language after sending the email.

Limitations and Things to Avoid When Using Language Override

The per-email spell check language override has several limitations that you should understand to avoid unexpected behavior.

The Override Applies to the Entire Message Body

The language override sets one proofing language for the whole email body. You cannot apply different languages to different paragraphs or sentences within the same message. If you need to include text in multiple languages, consider writing the foreign text in a separate email or using inline language marking, which the new Outlook does not support natively.

The Override Does Not Affect the Subject Line

The proofing language override applies only to the message body. The subject line continues to use the default proofing language. If you type foreign words in the subject line, they may still be flagged as misspelled.

The Override Resets After Sending or Closing

Once you send the email or close the compose window without saving, the language override is lost. The next new email reverts to the default proofing language. You must set the override again for each message that requires a different language.

Language Must Be Installed Before Use

If the language you want to use is not listed in the Set Proofing Language dialog, you need to install it first. Download the language pack from Windows Settings or install the Microsoft 365 Language Accessory Pack for your Office version. After installation, restart Outlook for the language to appear.

Spell Check May Not Work for Some Languages

Not all languages include a full spell check dictionary. Languages with limited proofing tools may still show underlines for correctly spelled words. Check the Microsoft documentation for your language to confirm spell check support.

Per-Email Language Override vs Global Proofing Language: Key Differences

Item	Per-Email Language Override	Global Proofing Language
Scope	Applies only to the current email message	Applies to all new emails and existing items
Setting location	Review tab > Language > Set Proofing Language in the compose window	File > Options > Mail > Spelling and Autocorrect > Proofing Language
Persistence	Resets after sending or closing the compose window	Remains until manually changed
Effect on subject line	Does not change subject line proofing	Changes subject line proofing as well
Effect on replies and forwards	Must be set again for each reply or forward	Applies automatically to replies and forwards

The per-email override is designed for occasional use when you need to write a single message in a different language. For frequent multilingual communication, consider changing the global proofing language or adding multiple language packs and using the language bar to switch quickly.

You can now set a different spell check language for any email in the new Outlook without altering your default settings. Use the Review tab and Set Proofing Language option for a one-time override or the language bar for frequent switching. For advanced scenarios, explore adding additional language packs through Windows Settings and configuring the Quick Access Toolbar with the Language command for faster access.