The short answer
Go to Settings › General › iPhone Storage to see what's using space and follow the recommendations. The biggest wins are usually turning on Optimize iPhone Storage for photos, offloading apps you don't use, deleting large videos and old message attachments, and emptying the Recently Deleted album.
When your iPhone runs out of space, you can’t take photos, install updates or download apps. The good news: iOS shows exactly what’s filling it up and suggests what to remove.
Your iPhone has two kinds of storage. Device storage is the space on the phone itself. iCloud storage is online space in your Apple Account. This guide is about device storage.
Step 1: See what’s using space
- Open Settings › General › iPhone Storage.
- Wait a moment for the bar to load. It shows space used by Apps, Photos, Media, Messages, iOS and System Data.
- Scroll down to see each app, sorted by size.
Apple notes that when storage gets low, iOS automatically removes some items you can download again, like temporary files and caches.
Step 2: Use the recommendations
Under the storage bar, iOS shows suggestions such as Offload Unused Apps or Review Large Attachments. Read each description, then tap Enable or tap the suggestion to review what will be removed.
Step 3: Optimize your photos
Photos and videos are usually the biggest category.
- Turn on Optimize iPhone Storage: go to Settings › [your name] › iCloud › Photos, turn on iCloud Photos (sometimes labeled Sync this iPhone), then choose Optimize iPhone Storage. Full-size originals stay in iCloud.
- Delete large videos you no longer need. In Photos, open the Videos media type to find them quickly.
- Empty Recently Deleted: deleted photos stay there for about 30 days. Open Photos › Recently Deleted, unlock it, then tap Select › Delete All.
Step 4: Offload or delete apps
In the app list under iPhone Storage, tap an app you rarely use:
- Offload App removes the app but keeps its data.
- Delete App removes the app and its data.
Games and streaming apps with downloaded episodes are often surprisingly large.
Step 5: Clear old message attachments
Photos and videos in Messages add up fast.
- In iPhone Storage › Messages, use Review Large Attachments to delete big files.
- In Settings › Apps › Messages › Keep Messages, choose 1 Year or 30 Days instead of Forever.
Step 6: Remove downloaded media
Check Music, Podcasts, TV and streaming apps for downloaded songs, episodes and movies you’ve already finished.
Step 7: Restart your iPhone
After freeing space, restart your iPhone. Temporary files and System Data often shrink afterwards.
If you still need more space
- Back up photos to a computer and remove them from the phone.
- Buy more iCloud storage if you use Optimize iPhone Storage and your iCloud is full.
- Next time, consider a model with more storage.
Related guides
Before you delete anything, back up your iPhone. A full iPhone can also block updates, so once you’ve cleared space, update your iPhone.
The bottom line
Start in Settings › General › iPhone Storage, follow the recommendations, optimize photos and offload unused apps. Those steps free up gigabytes for most people in a few minutes. Before big cleanups, make sure your iPhone is backed up.
Frequently asked questions
What's the difference between offloading and deleting an app?
Offloading removes the app itself but keeps its documents and data. The icon stays on your Home Screen, and tapping it reinstalls the app with your data intact. Deleting removes the app and its data.
Will Optimize iPhone Storage delete my photos?
No. It keeps your full-resolution photos and videos in iCloud and stores smaller versions on your iPhone. You need enough iCloud storage for your library, and the originals download when you open them.
What is “System Data” and can I delete it?
System Data includes caches, logs and other temporary files that iOS manages itself. You can't delete it directly. It often shrinks after a restart or after freeing space elsewhere.
Why you can trust this guide
- Based on official sources. The steps here are checked against the 2 official sources listed below, such as the help pages of the companies involved.
- Checked and dated. Last checked on November 10, 2026. We update guides when software or advice changes.
- Independent. No company paid for or reviewed this guide. We don't sell products, and ads never influence our advice.
- Open to corrections. Spotted an error? Tell us and we'll fix it. Read how we research.
Sources
- Apple Support — How to check the storage on your iPhone and iPad
- Apple Support — What's the difference between device storage and iCloud storage?
This guide is general information. Menus and features can change with software updates, and steps may differ on your device or version. Back up important data before making big changes. Read our disclaimer.
