How do I transfer data from an old iPhone 11 to a new iPhone 16?

If you have already set up the new iPhone then the data created during this period will be lost if you use any of the three processes given below

iPhone to iPhone, there are three ways,

1. Quick Transfer --> Use QuickStart to transfer data to a new iPhone, iPad or iPod ...
2. Restore from iCloud Backup, When you buy a new iPhone or iPad, you can get temporary iCloud storage to transfer data from your current device to your new one. --> Restore or set up your device from an iCloud backup - Apple ... or use Get temporary iCloud storage when you buy a new iPhone ...
3. Restore from iTunes backup --> Restore your iPhone, iPad, or iPod touch in iTunes on PC ...

Instead, try transferring data manually. One by One

1. If your old iPhone had iCloud enabled Optimised storage enabled then please do the same on the new device too. Check if you have enough iCloud Storage if you are using another Apple ID.
2. Messages, Media, Voice Memo, Keychain --> Turn on Messages in iCloud & iCloud Photos, Voice Memo, Keychain, and your content is automatically stored in iCloud and is available on all devices that use the same Apple ID including iCloud Drive
   1. 
3. Contacts --> Contacts are not stored on an iPhone nor on SIM, they are synced to  Google, iCloud, AOL, Exchange, Outlook, Yahoo or any Other. Use the email account that is in your old iPhone.
4. Notes, Reminders, Calendars --> You may sync all these from any of the email accounts that you have on your old iPhone. they can be synced using  Google, iCloud, AOL, Exchange, Outlook, Yahoo or any Other.
5. Any Specific Files --> Upload to Cloud Drives (iCloud Drive, Google Drive, OneDrive, DropBox, Flickr, box, AmazonDrive, Adobe Creative Cloud and Use Files app on your new iPhone too.
6. Apps & Settings --> In any way they have to be redownloaded using the App Store. Even you had used any of the 3 processes mentioned earlier. Apart from the Apps following will also not get transferred.
   1. Content from the iTunes and App Stores or PDFs downloaded directly to Apple Books
   2. Content synced from iTunes, like imported MP3s or CDs, videos, books, and photos
   3. Data already stored in iCloud, like iCloud Photos, iMessages, and text (SMS) and multimedia (MMS) messages
   4. Face ID or Touch ID settings
   5. Apple Pay information and settings
   6. Apple Mail data
   7. Apple Music
7. WhatsApp --> Take a backup of chats and media from within the WhatsApp App. Use the same Phone number as that of your earlier iPhone and activate the account in the new iPhone too. That's it. --> Transfer Whatsapp chat History from Andro… - Apple Community
8. Shazam Account --> Access your Shazams on all your devices or online - Apple ...
9. Airtag:
   1. Hold your AirTag near your iPhone or iPad, then tap Connect. · Name your AirTag, then tap Continue. · To register your AirTag with your Apple ID Add an AirTag in Find My on iPhone - Apple Support
   2. How to remove AirPods, AirTag, or another Find My network accessory or device from an Apple ID on iPhone, iPad, or iPod touch. Open the Find My ... If an item or device is connected to another Apple ID

Re: Retrieve information from old iPhone 11 download it to new iPhone 16

Re: iOS compatibility: If you have an iPhone back-up from the old phone:

You may or (may not) be able to:

Use the Finder, Apple Devices, or iTunes to transfer data from your ...

To just transfer data: See if you can:

Use a wired connection to transfer data to a new iPhone or iPad - Apple Support

We don't know any of the following:

Is your iPhone 11 operating normally at this time?

Do you have a current backup of the iPhone 11 on iCloud?

Do you have a current backup of the iPhone 11 on a Mac or PC?

Are you sure that the iPhone 16 is really "new"? We ask because Apple discontinued this model in September 2025, more than a year ago.

Even if you have one of the last iPhones 16 off the production line, if the phone is "new", it has been sitting in a warehouse somewhere for more than a year. This would not be good for the battery at all.

What is the Model Number of the iPhone 16 that you have?

Settings > General > About > Model Number