Outlook Adds Extra Spaces After Replying From Mobile: Fix

You reply to an email from the Outlook mobile app on your iPhone or Android phone, and when the recipient opens your reply on a desktop, they see extra blank lines, spaces, or paragraphs that you did not insert. This formatting problem usually occurs because the mobile app and the desktop client handle line breaks and paragraph markers differently, especially when the original message uses plain text or rich text formatting. This article explains why Outlook adds those extra spaces after replying from a mobile device and provides a set of fixes you can apply on both the mobile and desktop sides to stop the unwanted spacing.

Why Outlook Mobile Replies Add Extra Spaces

When you reply to an email from the Outlook mobile app, the app uses its own internal editor to compose the reply. The mobile editor converts line breaks and carriage returns into HTML paragraph tags or line-break tags differently than the desktop Outlook client. If the original message contains a mix of plain text and HTML formatting, the conversion process can insert extra blank lines between paragraphs or after your signature.

The most common technical root cause is the mismatch between the compose format on the mobile app and the read format on the desktop client. By default, the Outlook mobile app sends replies in Rich Text or HTML format. When the desktop client renders that HTML, it interprets double line breaks as separate paragraphs and adds an extra blank line for each. If you use a signature with multiple line breaks, each break becomes an additional space in the final email.

A second cause is the quote original message setting. On mobile, Outlook can include the original message below your reply. The formatting of that quoted text often includes extra line breaks that appear as empty spaces when viewed on desktop.

Steps to Fix Extra Spaces in Outlook Mobile Replies

Apply these fixes in the order shown. Start with the mobile app settings, then adjust the desktop settings if the problem persists.

Fix 1: Change the Reply Format on the Outlook Mobile App

1. Open the Outlook mobile app
   Tap the Outlook icon on your iPhone or Android device.
2. Go to Settings
   Tap your profile picture or the initials icon in the top-left corner. Then tap the gear icon at the bottom of the sidebar.
3. Select the email account
   Under Mail Accounts, tap the email address that is adding the extra spaces.
4. Change Reply Format to Plain Text
   Scroll to the Compose section. Tap the option labeled Reply Format or Compose Format. Select Plain Text. This forces the app to send replies without HTML paragraph tags.
5. Send a test reply
   Reply to a message from your mobile device and check the result on your desktop Outlook. The extra spaces should be gone.

Fix 2: Remove Extra Blank Lines From Your Mobile Signature

1. Open the Outlook mobile app
   Tap the Outlook icon.
2. Go to Settings and select your account
   Tap your profile picture, then the gear icon. Tap the email account.
3. Edit the signature
   Under the Signature section, tap Signature. The current signature appears with any blank lines visible.
4. Delete unnecessary blank lines
   Place the cursor after the last character of each line and press the backspace key to remove empty lines. Keep only one line break between your name and your contact details.
5. Save and test
   Tap the back arrow or Save button. Send a test reply from mobile and verify the spacing on desktop.

Fix 3: Adjust the Desktop Outlook Compose Format

1. Open Outlook on your Windows desktop
   Launch the Outlook desktop application.
2. Go to File > Options
   Click File in the top-left corner, then click Options at the bottom of the left pane.
3. Open the Mail tab
   In the Outlook Options dialog, click Mail in the left sidebar.
4. Change Compose Messages in This Format
   Under the Compose Messages section, locate the dropdown labeled Compose messages in this format. Select HTML or Plain Text. Do not select Rich Text if you are seeing extra spaces, because Rich Text uses paragraph markers that add blank lines.
5. Click OK
   Click OK to save the change. Restart Outlook for the setting to take effect.

Fix 4: Disable the Original Message Quote in Replies

1. Open the Outlook mobile app
   Tap the Outlook icon.
2. Go to Settings and select your account
   Tap your profile picture, then the gear icon. Tap the email account.
3. Find the Quote Original Message setting
   Scroll to the Compose section. Look for Quote original message or Include original message in replies.
4. Turn off the quote
   Toggle the switch to Off. This removes the quoted text from all replies, eliminating the extra line breaks that come with it.
5. Test a reply
   Send a test reply from mobile. The recipient will see only your reply text without the original message and without extra spaces.

If Extra Spaces Still Appear After the Main Fix

Extra spaces appear only when replying to a specific sender

The sender may be using a different email client that inserts its own line breaks when rendering your reply. Ask the recipient to view the email in plain text mode or forward the email to a different account to see if the spaces persist. If the spaces disappear in another client, the issue is on the recipient side, not yours.

Extra spaces appear after pasting text into a mobile reply

When you copy text from a web page or a notes app and paste it into an Outlook mobile reply, the copied text may carry hidden formatting tags. Those tags become extra blank lines after sending. Use the Paste as Plain Text option in the mobile app if available, or paste the text into a plain-text editor first and then copy it again.

Extra spaces appear only on Android devices

Some Android keyboards add a double space after a period by default. This double-space setting inserts an extra blank line after each sentence. Go to your Android keyboard settings and disable the double-space period shortcut. Then compose a test reply without using the period key to confirm the fix.

Outlook Mobile Reply Formats: What Each Setting Does

Item	Rich Text (Default)	Plain Text
Formatting support	Bold, italics, colors, fonts	No formatting
Line break behavior	Converts line breaks to HTML paragraph tags, which add extra spaces	Uses single line breaks with no extra spacing
Signature compatibility	Can include images and multiple line breaks that create gaps	Only text with simple line breaks
Best for	Formal emails that need styling	Quick replies and internal messages where spacing must be clean

The extra spaces problem disappears when you set the mobile reply format to Plain Text. If you need formatting for specific emails, switch back to Rich Text only for those messages and test the result before sending.