Why is the number of unread mails different on iphone, ipad, and mac

Hello ctscmiller,

To answer your question, it will completely depend on when those devices sync with your mail servers.

If you think there might be an issue, these are great places to start:

• Troubleshoot email problems in Mail on Mac - Apple Support
• If you can't receive email on your iPhone, iPad, or iPod touch - Apple Support

Specifically for your iPhone and iPad:

By default, Fetch New Data settings are based on what's provided by your email service. If Push isn't available as a setting, your account will default to Fetch. These settings affect how your device receives email. To adjust these settings:

1. Go to Settings > Mail, then tap Accounts.

2. Tap Fetch New Data.

3. Choose a setting — like Automatically or Manually — or choose a schedule for how often the Mail app fetches data.

With iOS 11 and later, and iPadOS, Automatically is set by default. Your device will fetch new data in the background only when your device is charging and connected to Wi-Fi.

Make sure that your Notification settings are correct for the Mail app:

1. Go to Settings, then tap Notifications.

2. Tap Mail, then tap an email account.

3. Adjust your Alerts, Sounds, and Badges.

Thanks and have a great day.