When you add multiple email accounts to the Outlook mobile app, the app automatically selects a default sending account for new messages. This default is often the first account you added, not necessarily the one you use most frequently. The default sending account determines which email address appears in the From field when you tap Compose for the first time after opening the app. This article explains how to change that default account on both iOS and Android devices so every new message starts with the correct sender address.
Key Takeaways: Setting the Default Sending Account in Outlook Mobile
- Outlook Mobile Settings > Default Account: Lets you choose which email account appears first in the From field when composing a new message.
- iOS Settings > Mail > Default Account: Overrides the Outlook app default if you use the iOS Mail app integration, but the Outlook app uses its own setting.
- Android Settings > Apps > Outlook > Default Account: Not available — the default is set only inside the Outlook app under Settings.
Understanding the Default Sending Account in Outlook Mobile
The Outlook mobile app for iOS and Android supports multiple email accounts from different providers or within the same organization. When you open the app and tap the Compose button, the From field automatically shows the address from one account. That account is the default sending account.
The app determines the default based on the order in which accounts were added. The first account you configure becomes the default. You can change this default at any time without removing or re-adding accounts. The setting is stored locally on the device and does not sync with other Outlook clients or the web version.
How the Default Affects Replies and Forwards
The default sending account only affects new messages. When you reply to or forward an email, Outlook automatically uses the same account that received the original message. This behavior is separate from the default account setting. You cannot change the reply behavior through the default account setting.
Prerequisites for Changing the Default
You need at least two accounts added to the Outlook mobile app. The accounts can be any combination of Outlook.com, Office 365, Exchange, Gmail, Yahoo, or IMAP accounts. No administrator permissions are required. The change takes effect immediately after you save the setting.
Steps to Change the Default Sending Account on iOS
- Open the Outlook app on your iPhone or iPad
Make sure you are signed in with at least two accounts. If you see the inbox, you are ready. - Tap your profile icon in the top-left corner
The profile icon shows your initials or a photo. This opens the Settings menu. - Tap the gear icon to open Settings
The gear icon is located at the bottom of the profile panel. This opens the main Settings screen. - Tap Default Account under the Mail section
You see a list of all accounts configured in the app. The current default has a checkmark next to it. - Select the account you want as the default
Tap the account name. A checkmark appears next to it. The setting saves automatically. - Return to the inbox and tap Compose to verify
The From field now shows the account you selected. If it does not, close and reopen the app.
Steps to Change the Default Sending Account on Android
- Open the Outlook app on your Android phone or tablet
Ensure you are signed in with at least two accounts. The inbox displays when ready. - Tap your profile icon in the top-left corner
This opens the account panel with your photo or initials. - Tap the gear icon to open Settings
The gear icon is at the bottom of the panel. The Settings screen appears. - Tap Default Account under the Mail section
You see all accounts listed. The current default has a checkmark. - Tap the account you want to set as default
A checkmark moves to that account. The change is saved immediately. - Press Back and tap Compose to confirm
The From field displays the newly selected account. If it does not, restart the app.
If the Default Account Setting Does Not Work
The From Field Still Shows the Old Account After Changing the Setting
This usually happens because the app cache is stale. Force close the Outlook app and reopen it. On iOS, swipe up from the bottom and swipe the Outlook card away. On Android, go to Settings > Apps > Outlook > Force Stop. Then open Outlook again and tap Compose.
The Default Account Option Is Grayed Out or Missing
This occurs when only one account is configured. Add a second account to the app. The Default Account option appears only when two or more accounts are present. If you have multiple accounts and the option is still missing, update the app to the latest version from the App Store or Google Play Store.
The Default Account Resets After an App Update
Some app updates reset local settings. After updating, open Settings and check the Default Account option. Set it again if needed. This is a known behavior in older versions of the app. Keeping the app updated reduces the frequency of this reset.
Outlook Mobile Default Account vs iOS Mail Default Account
| Item | Outlook Mobile Default Account | iOS Mail Default Account |
|---|---|---|
| Where to set | Outlook app Settings > Default Account | iOS Settings > Mail > Default Account |
| Affects which app | Outlook mobile app only | iOS Mail app only |
| Number of accounts required | 2 or more in Outlook | 2 or more in iOS Mail |
| Syncs across devices | No — set per device | No — set per device |
| Affects replies and forwards | No — only new messages | No — only new messages |
You now know how to set the default sending account in the Outlook mobile app on both iOS and Android. Next time you add a new account, check the Default Account setting so the correct address appears when you compose a message. For advanced control, you can also change the From address per message by tapping the From field before sending.