> ## Content Index > Fetch the complete content index at: https://www.techbetweenthelines.com/llms.txt > Use this file to discover other available public pages before exploring further. # Setting Up a New iPhone? Do It in This Order - URL: https://www.techbetweenthelines.com/how-to-set-up-a-new-iphone-ios-27/ - Published: 2026-10-11T23:34:29.000Z - Updated: 2026-10-11T23:35:33.000Z - Description: Most new iPhone headaches come from doing things in the wrong order. Here is the right one, from a few days before to the day you hand the old phone on. - Author: Justin - Tags: Tips & Tricks, Apple OS 27, Apple Most new iPhone problems are not problems with the new iPhone. They are problems with the order things were done in: the old phone erased before the authenticator codes moved, the number transferred before the carrier was ready, the Watch unpaired for no reason. Get the order right and setup day is boring, which is exactly what you want. This is that order for iOS 27, from a few days before to the day you hand the old phone on. ## A few days before ### Update and back up the old iPhone Install the latest iOS on the old phone in **Settings > General > Software Update**. Moving an eSIM directly between iPhones needs iOS 18.4 or later on both. Then back up at **Settings > \[your name\] > iCloud > iCloud Backup > Back Up Now** and check the time under the button. ### Out of iCloud space? Borrow it free Apple lends you enough temporary iCloud storage for a full backup when you buy a new iPhone. Go to **Settings > General > Transfer or Reset iPhone** and tap Get Started under Prepare for New iPhone. You get 21 days to restore it, and Keep My Backup Longer adds 21 more if the phone has not arrived. ![Transfer or Reset iPhone screen in iOS 27](https://www.techbetweenthelines.com/content/images/2026/10/tbtl-ios27-s09.jpg) ![iCloud Backup settings in iOS 27](https://www.techbetweenthelines.com/content/images/2026/10/tbtl-ios27-n15.jpg) Transfer or Reset iPhone, where Prepare for New iPhone lends free iCloud space, and the iCloud Backup screen. ### Know your SIM situation iPhone 18 Pro, 18 Pro Max and the iPhone 17 lineup are eSIM only when bought in the U.S., Canada, Mexico, Japan and several other countries, and iPhone Air and iPhone Duo are eSIM only everywhere. If you are coming from a physical SIM, check that your carrier supports transferring it. ## Setup day ### Use Quick Start, and choose the right transfer Put both phones on power side by side, with Wi-Fi and Bluetooth on, and turn on the new one. Follow the prompt on the old iPhone. When asked how to transfer, **Download from iCloud** lets you use the new phone right away while everything downloads in the background; transferring directly from the old iPhone makes you wait until it finishes. Choose iCloud if your backup is current. ![The New iPhone Playbook cover](https://public-files.gumroad.com/x75vd4u2rbntfgdezqh27r4tm5qc) The full playbook Want every step and checklist? Get The New iPhone Playbook. Setup day step by step, the first hour settings, a charger cheat sheet for every current iPhone, and printable checklists. [Get the playbook, $12](https://techbetweenthelines.gumroad.com/l/new-iphone-playbook?ref=techbetweenthelines.com)PDF, instant download, free updates. ### Move your number If setup does not offer it, go to **Settings > Cellular > Set Up Cellular** afterward and choose Transfer From Nearby iPhone. Apple's requirements: carrier support, both iPhones on the same Apple Account, and iOS 18.4 or later. ### Bring the Apple Watch across If you restore the new iPhone from a recent backup, it will ask whether to use your Apple Watch. Keep the watch unlocked on your wrist and tap Continue. There is no need to unpair it first. ## The first hour Turn on **Stolen Device Protection** (Settings > Face ID & Passcode) and set it to Always, make sure **Find My** is fully on, turn on automatic updates, and set a **charge limit** in Settings > Battery > Charging if your iPhone is a 15 or later. Then give the Action button a job other than Silent mode. ![Find My iPhone settings in iOS 27](https://www.techbetweenthelines.com/content/images/2026/10/tbtl-ios27-p24.jpg) ![Battery Charging settings with Charge Limit in iOS 27](https://www.techbetweenthelines.com/content/images/2026/10/tbtl-ios27-p20.jpg) Find My iPhone, which stays on while Stolen Device Protection is on, and the charge limit in Settings > Battery > Charging. ## The first week Expect the new phone to run warm and drain faster for a few days while it downloads and indexes everything; Apple says the same kind of background work after a major update temporarily affects battery life and heat. Before you trust the new phone, open every banking and authenticator app. Many need you to sign in again or move codes, and you want the old phone working while you do it. For fast charging, the adapter matters: Apple says the iPhone 18 Pro models reach 50 percent in about 15 minutes with a 60W or higher USB-C adapter that supports Adjustable Voltage Supply, while iPhone 17, 17 Pro and 17 Pro Max need 40W or more for their fastest charge. There is no adapter in the box. ## Only then: the old iPhone Once the new phone has everything, including a working phone line, unpair the Watch if it is still on the old phone, sign out of your Apple Account, and erase it at **Settings > General > Transfer or Reset iPhone > Erase All Content and Settings**, choosing to erase the eSIM too. Apple says erasing turns off Find My and Activation Lock. If you are trading in with Apple by mail, Apple needs to receive the old phone within 14 days of when you receive the new one, so ship it early. ![The New iPhone Playbook cover](https://public-files.gumroad.com/x75vd4u2rbntfgdezqh27r4tm5qc) The New iPhone Playbook Switch without losing a thing. Backups, eSIM, Apple Watch, Android, AppleCare, chargers and the safe way to sell the old one, all in order. Built on Apple's own documentation for iOS 27. [Get the playbook, $12](https://techbetweenthelines.gumroad.com/l/new-iphone-playbook?ref=techbetweenthelines.com)PDF, instant download, free updates. Sold through Gumroad. Related: if something misbehaves on the new phone, our [iOS 27 problems and fixes page](https://www.techbetweenthelines.com/ios-27-problems-and-fixes/) tracks every known issue. Read us first See more TBTL when you search Google Add Tech Between the Lines as a preferred source and our Apple coverage shows up more often in your Top Stories. It takes one tap, and you can change it anytime. [Prefer TBTL on Google](https://www.google.com/preferences/source?q=techbetweenthelines.com&ref=techbetweenthelines.com)