You can't upgrade Mac storage after you buy on almost any Mac Apple sells today. Apple's own store says so: "Storage can't be upgraded later" for the MacBook Air and MacBook Pro, and "Internal storage can't be upgraded later" for the Mac mini and Mac Studio.
The amount you choose at checkout is the amount the Mac keeps for its whole life.
There are a few exceptions. Apple documents installing new SSD modules in the Mac Pro (2019) and Mac Pro (2023), and small companies sell modules for the Mac mini that you fit yourself, at the cost of Apple's warranty for any damage the work causes. Some older Intel Macs had drives a repair shop could replace.
For everyone else, the real options are outside the Mac: an external SSD on a fast port, big libraries moved to it the way their apps support, network storage, iCloud, or trading the Mac in for one with more room. Each suits some things and not others, and this post goes through them all.
Before you spend anything, find out what's actually filling the disk. A lot of space usually goes to things you can remove or move in an afternoon.
Which Macs can you upgrade storage on?
Apple answers this on its store. When you choose a Mac's storage, the help panel Not sure how much storage to get? asks "Can I add storage later?" and answers no, with advice to buy more now if you think you'll need it.
| Mac | Storage you can choose at purchase | Can you add storage later? |
|---|---|---|
| MacBook Neo | 256 GB or 512 GB | No |
| MacBook Air (M5) | 512 GB to 4 TB | No, Apple says |
| MacBook Pro (M5 family) | 1 TB to 8 TB | No, Apple says |
| iMac (M4) | 256 GB to 2 TB | No |
| Mac mini (M6, M5 Pro) | 256 GB to 8 TB | No, Apple says; third-party modules exist |
| Mac Studio (M5 Max, M5 Ultra) | 512 GB to 16 TB | No, Apple says |
| Mac Pro (2019, 2023) | Varies | Yes, with Apple-documented SSD modules |
The ranges come from Apple's tech specs pages in October 2026. Apple counts a gigabyte as a billion bytes and notes that the formatted capacity is less, which is why a 512 GB Mac never shows 512 GB free, even on day one.
MacBook Neo, MacBook Air and MacBook Pro
Apple's laptops have their storage built in. On the store, Apple's answer for the MacBook Air and MacBook Pro is the same: storage can't be upgraded later. There's no panel to open and no slot to fill.
The MacBook Neo is the most limited: it comes with 256 GB or 512 GB and nothing else. The 512 GB model costs more, but it also adds the keyboard with Touch ID, so the price gap isn't storage alone.
iMac
The iMac with M4 offers 256 GB to 2 TB when you buy it, depending on the model. Like the laptops, it's a sealed design with the storage built in, and its specs list no way to change it afterwards. Its four-port models give you more Thunderbolt ports for external drives.
Mac mini and Mac Studio
Both have their storage on a separate module inside the case, which is why you'll read that they're "upgradeable". Apple's store disagrees: for both, it says internal storage can't be upgraded later.
Apple's own repair manual for the Mac mini (2024) does include an SSD module procedure, as part of its Self Service Repair program. That's a repair, replacing a part, not an upgrade path Apple offers on its store.
Mac Pro
The Mac Pro is the one Mac where Apple documents adding storage. Its support articles for the Mac Pro (2019) and Mac Pro (2023) explain how to install or replace SSD modules, using modules made for that model and Apple Configurator on a second Mac.
Apple no longer lists the Mac Pro on its Mac page; its old address now leads back to the Mac lineup. If you already own one, though, it remains the only Mac with an Apple-supported way to grow its internal storage.
Why can't you just swap the SSD?
On a Mac with Apple silicon, the storage controller is part of the chip itself. iFixit's Mac mini (2024) guide notes that the module looks like a standard M.2 SSD but has no controller, so standard M.2 SSDs won't work in it.
The storage is also tied to the chip's Secure Enclave. Apple's platform security guide explains that internal storage on Macs with Apple silicon, and on Intel Macs with the T2 chip, is encrypted with keys from that hardware. That's why even Apple's own Mac Pro modules have to be paired and set up with Apple Configurator.
Third-party SSD upgrade kits
Because the Mac mini's storage sits on a module, a few small companies sell larger replacement modules. They're real products, but they're not Apple's, and fitting one is a project, not a plug-in.
What's on sale for the Mac mini?
In May 2025, the German tech site heise reported that a Hong Kong vendor was selling modules for both the M4 and M4 Pro Mac mini, in sizes up to 8 TB, and that another seller had offered modules for the base M4 first. It described the work as suited to somewhat experienced hobbyists.
Fitting one means opening the Mac, swapping the module, then setting the Mac up again from another computer in DFU mode, the mode used for firmware restores. The new module starts empty, so everything comes back from a backup. heise also noted that the memory chips' source was unclear and the modules appeared to be reverse-engineered.
What happens to the warranty?
Apple's limited warranty for Macs lists what it doesn't cover. Two of its exclusions apply directly: damage caused by service, "including upgrades and expansions", performed by anyone who isn't Apple or an Apple Authorized Service Provider, and a Mac that has been modified to alter its functionality or capability without Apple's written permission.
Consumer law in your country may still give you rights, but anything the upgrade damages, or that Apple decides it damaged, isn't Apple's to fix for free under its warranty. If you have AppleCare, read its terms too before you open the case.
Is a third-party module worth it?
That depends on how much you trust your hands and the seller. A module failure takes the Mac's startup disk with it, and you'd be depending on a small vendor's own warranty instead of Apple's.
For most people, an external SSD gives the same extra room with none of the risk: nothing to open, nothing to restore, and it moves to your next Mac. If you do go ahead, back up everything first, because the restore erases the Mac.
Intel Macs: the older exceptions
Before Apple silicon, the answer depended on the model. A few Intel Macs had storage you could replace, and one still does with Apple's documented steps.
Mac Pro (2019)
Apple documents installing or replacing the SSD modules in the Mac Pro (2019). Its modules are paired to and encrypted by the T2 Security Chip, so after fitting them you restore the T2's firmware with Apple Configurator on another Mac with macOS 10.14.6 or later. Apple warns that once pairing starts, the old SSD's data can't be recovered.
Intel Macs with the T2 chip
Apple lists the Macs with its T2 Security Chip: Intel MacBook Pro and MacBook Air models from 2018 through 2020, the iMac (Retina 5K, 27-inch, 2020), the iMac Pro, the Mac mini (2018) and the Mac Pro (2019).
Apple's platform security guide groups them with Apple silicon Macs: their internal storage is connected to the Secure Enclave and encrypted with its hardware keys. In practice, that ties the storage to the Mac, as on Apple silicon.
Older Intel Macs
Apple's security guide treats Macs from before the T2 chip separately, because their drives aren't encrypted by dedicated hardware. Some of those models had drives a repair shop could reach and replace; others didn't. Whether yours can take a bigger drive depends on the exact model, so check a repair guide for it before you buy parts.
Should you upgrade an old Intel Mac?
Only if the Mac still does what you need. A bigger drive gives an old Mac more room, but not a faster chip or a newer macOS, and the work usually means opening a case that wasn't designed to be opened.
If you're weighing a drive upgrade against a new Mac, price the new Mac with the storage you'd actually need, as in the next section. Sometimes the old Mac plus an external drive is the better deal for a few more years.
What Apple charges for more storage when you buy
Since you can't add storage later, the choice at checkout is the one that counts. Here's what each step cost on Apple's US store as of October 2026, comparing standard configurations that differ only in storage.
| Storage step | Configurations compared | Extra cost |
|---|---|---|
| 256 GB to 512 GB | Mac mini, M6, 16 GB memory: $899 and $1,099 | $200 |
| 512 GB to 1 TB | 15-inch MacBook Air, M5, 16 GB: $1,499 and $1,799 | $300 |
| 512 GB to 1 TB | 13-inch MacBook Air, M5, 24 GB: $1,499 and $1,799 | $300 |
| 1 TB to 2 TB | 14-inch MacBook Pro, M5 Pro, 24 GB: $2,499 and $2,999 | $500 |
| 256 GB to 512 GB | MacBook Neo: $699 and $799 | $100, with Touch ID added |
- 256 GB to 512 GB, Mac mini200 USD
- 512 GB to 1 TB, MacBook Air300 USD
- 1 TB to 2 TB, MacBook Pro500 USD
Prices from Apple's US online store in October 2026, comparing standard configurations of the same model, chip and memory that differ only in storage. Other countries and future prices differ.
How to read these prices
Each step doubles the storage, and in these examples each costs more than the last. Prices vary by country and change with new models, so check the store on the day you buy. Education pricing and refurbished Macs change the numbers too, but not the rule that storage can't be added later.
Notice what a step pays for: built-in storage that's always there, as fast as the Mac's own disk, with nothing to carry or plug in. That's worth more to some people than others.
How much storage should you buy?
Apple's own advice on the store is to look at what you use today: open System Settings › General › Storage on your current Mac, and if you're near the limit, choose more. The post on whether 256 GB is enough for a Mac goes through realistic amounts for each kind of use.
A useful test: what will you add over the years you keep the Mac? Photos, video projects, games and local AI models grow; documents and email rarely matter. If you can name a large, growing thing, buy the next step up.
Check what you use today
Storage settings show a bar of categories, but the categories are broad. To see what fills your current Mac folder by folder before you choose, check storage on your Mac with Storage settings and Finder, or with a disk map.
If most of the space is a photo library or video projects, an external drive may serve you better than a bigger internal one. If it's apps and their data, which really want to live inside the Mac, the bigger internal disk earns its price.
External SSDs: the closest thing to an upgrade
An external SSD is how most people add storage to a Mac they already own. Plugged into a fast port, a good one is quick enough for photo libraries, video projects, games and archives.
Which port should the drive use?
The port sets the ceiling. Apple's tech specs list these maximum speeds for current Macs; a drive only reaches them if the drive and the cable are as fast.
| Port | Up to | Current Macs that have it |
|---|---|---|
| Thunderbolt 5 | 120 Gb/s | Mac Studio, MacBook Pro with M5 Pro or Max, Mac mini with M5 Pro |
| Thunderbolt 4 or USB 4 | 40 Gb/s | MacBook Air, iMac, MacBook Pro with M5, Mac mini with M6 |
| USB 3 | 10 Gb/s | MacBook Neo, the Mac mini's front ports |
| USB 2 | 480 Mb/s | MacBook Neo's second port |
On the MacBook Neo, the two ports look alike but aren't: one is USB 3, the other USB 2. Plug the drive into the USB 3 port. On the Mac mini, the rear Thunderbolt ports are much faster than the front USB-C ports.
SSD or hard disk?
For anything you open often, an SSD. Apple's Disk Utility guide says its file system, APFS, is optimized for flash and SSD storage, though it also works on hard disks. A hard disk holds more for the money and suits archives you rarely open.
Some software is fussy about slow drives. Steam's support page, for one, recommends against installing Steam itself on an external hard drive because of performance, though it supports game libraries on other drives.
How should you format it?
A new drive often comes formatted for Windows. For a drive used with Macs, choose APFS: Apple's apps want it, or Mac OS Extended, for their libraries. The post on APFS, Mac OS Extended and exFAT explains which to choose and how to erase a drive in Disk Utility.
Erasing deletes everything on the drive, so copy anything you need off it first.
What can live on an external drive?
Big libraries, finished projects, game installs, virtual machines and local AI models move well. Apps' everyday data, your home folder and iCloud Drive don't. The post on what to move to an external drive goes through each one and how its owner supports the move.
Can you install apps on an external drive?
Some. The App Store has a setting for it: App Store › Settings › Download and install large apps to a separate disk. Apple says it puts apps larger than 1 GB on an external drive of your choice, and that the drive must be formatted as APFS.
That suits large games and pro apps. Keep everyday apps on the Mac: an app on a drive that isn't connected simply isn't there.
Move big libraries the supported way
The biggest space savings usually come from a few large libraries. Apple's apps, and many others, have a documented way to keep their libraries on another drive. Use it, rather than dragging folders out of your Library by hand.
Photos
Apple's steps are short: quit Photos, drag the library to a drive formatted as APFS or Mac OS Extended (Journaled), open it there, and set it as the System Photo Library if you use iCloud Photos. Apple warns against SD cards, USB flash drives, network drives and your Time Machine drive.
The post on moving the Photos library to an external drive covers the checks before and after, and what happens if the drive isn't connected.
Music, iMovie and Final Cut Pro
Music can keep files on an external drive: in Music › Settings › Files, click Change to choose a new place for imported files, or turn off copying files into the Media folder. Apple says not to move the Music folder itself.
iMovie and Final Cut Pro libraries move with Apple's steps too. Apple says an iMovie library needs a drive formatted as APFS or Mac OS Extended (Journaled), and Final Cut Pro asks for APFS. Neither can live on a Time Machine drive.
Logic Pro's sound library
Logic Pro 12 keeps all its sounds in one bundle in your Music folder, and Apple says you can drag it to another drive at any time. Older versions use Logic Pro › Sound Library › Relocate Sound Library, and for those Apple warns not to rename the drive afterwards, or Logic Pro won't find the sounds.
Games and video caches
Game launchers let you add a library on another drive and move games to it; Steam does this in Settings › Storage. The post on Steam games and the space they take covers the details.
Video editors can put their caches on a fast external drive too. The post on DaVinci Resolve's cache files explains where Resolve keeps them and how to point them elsewhere.
What shouldn't you move?
Leave your home folder, its Library folder and iCloud Drive where macOS put them. Apps expect their settings and data there, and macOS offers no setting to keep iCloud Drive on another disk. Moving them by hand risks apps losing their data and sync breaking.
Network storage and the cloud
If your Mac stays at home or in one office, storage on the network can hold what doesn't need to travel. If it travels, the cloud can hold files you open now and then.
A NAS or another Mac on your network
A network-attached storage device, or NAS, is a box of drives on your network. Finder connects to it with Go › Connect to Server, and you can keep archives, finished projects and media there. Time Machine can back up to a NAS that supports Time Machine over SMB.
Apple sets limits: Apple Filing Protocol (AFP) isn't supported in macOS 27, so use SMB. And Apple warns against keeping a Photos library or an iMovie library on a network drive. Treat the network as a place for files, not live libraries.
iCloud Drive and iCloud Photos
iCloud can free space without moving anything by hand. With Optimize Mac Storage on, macOS keeps older iCloud Drive files only in iCloud when space runs low, and iCloud Photos can keep smaller versions of photos on the Mac.
It costs a subscription instead of a one-time payment. In the US, iCloud+ costs $0.99 a month for 50 GB, $2.99 for 200 GB, $9.99 for 2 TB, $29.99 for 6 TB and $59.99 for 12 TB, according to Apple as of October 2026.
The post on iCloud Drive taking up space explains how Optimize Mac Storage decides what to remove, and why it acts only when space runs low.
Is the cloud a replacement for internal storage?
Not entirely. Files kept only in the cloud need a connection to open, and large files take time to download. It works best for documents and photos you browse, less well for video projects or games you work on all day.
For comparison, the $500 that Apple charged to go from 1 TB to 2 TB on a MacBook Pro in October 2026 would pay for about 50 months of a 2 TB iCloud+ plan at US prices. Which is better depends on how long you keep the Mac and whether you'd pay for iCloud anyway.
Free up space before you spend
A full Mac often has a lot of space you can get back for free. Look before you buy a drive or a new Mac.
What usually fills a Mac?
Apps, photo and video libraries, downloads you forgot, message attachments, phone backups and caches. On developer Macs, toolchains, simulators and package caches. Storage settings' categories give a first view, and a disk map shows which folders are really large.
Remove what you don't use
Apps you no longer open are the easiest win, especially large ones that bring their own data. The post on apps taking up space shows how to see each app's real size and remove it properly.
If you write code, old SDKs, simulators and package caches can take tens of gigabytes. The post on uninstalling development tools you no longer use covers removing them with each tool's own uninstaller.
Use Storage settings' recommendations
System Settings › General › Storage offers three recommendations. Store in iCloud keeps files, photos and messages in iCloud. Optimize Storage removes Apple TV movies and shows you've watched and keeps only recent Mail attachments when space is needed. Empty Trash automatically erases items that have been in the Trash for more than 30 days.
Remember that removing files doesn't make a Mac faster. It frees space, which matters when macOS needs room to update or apps need room to work.
Trading in or selling for a Mac with more storage
Sometimes the honest answer is a new Mac. If the disk is full of things you need on the Mac itself, every day, an external drive is a workaround, not a fix.
When does a new Mac make sense?
When the space problem is apps and their working data, which belong inside the Mac. When you're carrying a drive everywhere and it's become a nuisance. Or when the Mac is old enough that you'd be replacing it soon anyway.
Apple Trade In gives credit toward a new Mac based on the old one's model and condition. Apple says you need the serial number for an accurate estimate; it's in Apple menu › About This Mac.
Before you trade it in
Back up first, with Time Machine or by copying your files. On a Mac with Apple silicon or the T2 chip, Apple's Disk Utility guide says to use Erase Assistant to get the Mac ready to trade in, sell or give away, rather than erasing the disk yourself.
On the new Mac, Migration Assistant moves your documents, apps, accounts and settings from the old Mac or a Time Machine backup. Clear out what you don't need before migrating, so you don't fill the new disk with the old Mac's leftovers.
Buy more than you think you need
The new Mac's storage is fixed too. Use the prices above and what you measured on the old Mac to pick a size with room for the years you'll keep it.
A worked example: a full 512 GB MacBook Air
Here's how the options play out on one made-up but typical Mac. Say you have a 512 GB MacBook Air, Storage settings show about 40 GB available, and macOS has started warning you before updates.
Step one: find out what's there
You look at the disk folder by folder. The Photos library is 190 GB, mostly video. Steam games take 85 GB, two finished video projects 60 GB, and the Downloads folder 25 GB of installers and old archives. Apps and everything else make up the rest.
Nothing here needs a bigger internal disk. It needs a few things moved and a few things removed.
Step two: remove and move
The installers and archives you've already used go to the Trash: 25 GB back once you empty it. The two finished projects are copied to an external SSD, checked, and then removed from the Mac: 60 GB more.
You format the SSD as APFS and move the Photos library with Apple's steps, keeping the original until the copy has worked for a couple of days. Then you add a Steam library on the SSD and move the games you play less often there.
Step three: count the result
That's more than 300 GB free instead of 40 GB, with nothing deleted that you wanted. The cost is an external drive, and the habit of plugging it in before you open Photos.
The drive now holds the only copy of your library and projects, so it needs a backup too: a second drive for Time Machine, or iCloud Photos for the library.
What would the upgrade have cost?
To get the same room inside the Mac, you'd have needed a new MacBook Air with 1 TB. In October 2026 that configuration cost $300 more than the same model with 512 GB on Apple's US store, on top of the price of the new Mac itself.
If instead most of the 512 GB had been apps and their data, which belong on the internal disk, the external drive wouldn't have helped much. That's the case where trading up to more internal storage is the real fix.
Mistakes to avoid
| Don't | Why | Instead |
|---|---|---|
| Buy the smallest storage and plan to upgrade later | Apple's store says storage can't be upgraded later | Buy for the years you'll keep the Mac |
| Fit a third-party module without a backup | The restore erases the Mac | Back up everything first |
| Expect a standard M.2 SSD to fit | Apple silicon modules have no controller of their own | Use modules made for that Mac |
| Drag app folders out of your Library | Apps lose their data and sync breaks | Use each app's own setting to move it |
| Keep the only copy on one external drive | Drives fail and get lost | Back it up to a second drive |
| Plug a fast SSD into a USB 2 port | It runs at a fraction of its speed | Use the fastest port the Mac has |
Don't confuse memory with storage
Memory, or RAM, is what apps use while they run; storage is where files live. Apple's store says memory can't be added later either. Running out of one doesn't mean you need more of the other, so check which one Storage settings or Activity Monitor says is short.
How the app does it
Wombit doesn't add storage, but it shows where yours went, so you can decide whether you need more. It scans the whole disk or any folder, reading only names, sizes and dates, and shows the result as a map with a list and search. File names and paths never leave your Mac.
Every item the catalog knows gets an explanation and a level. Only Safe items, which their owner recreates with nothing lost, start checked and count in the headline number. Libraries, phone backups and large old files are Review first, because they may be the only copy, and the Photos library is Managed by macOS: explained, never moved.
An honest space meter in the app and the menu bar shows what's available. System Data, explained splits that category into named buckets and shows how much it couldn't explain.
The analyzer, the map, the explanations and the space meter are free. Cleanup, the uninstaller, the Apple Data actions for iPhone backups, installers and large old files, and What Changed with alerts when space runs low are PRO: one payment of $4.99 with lifetime access.
Every Pro tool's review is free to open, so you see what would go and why before you buy.
Frequently asked questions
Can I add more storage to my MacBook after buying it?
Not inside it. Apple's store says storage can't be upgraded later on the MacBook Air and MacBook Pro, and the MacBook Neo is the same. You can add space outside the Mac with an external SSD, network storage or iCloud.
Can you upgrade the SSD in a Mac mini?
Apple says no: its store says the Mac mini's internal storage can't be upgraded later. Small third-party vendors sell replacement modules, but fitting one means opening the Mac and setting it up again from another computer, and Apple's warranty doesn't cover damage from that work.
Which Mac has upgradeable storage?
The Mac Pro. Apple documents installing or replacing SSD modules in the Mac Pro (2019) and Mac Pro (2023), using modules made for that model and Apple Configurator on a second Mac. Apple no longer lists the Mac Pro among the Macs it sells.
Why can't I put a normal M.2 SSD in a Mac?
On Apple silicon Macs, the storage controller is built into the chip, so the storage module has none of its own. A standard M.2 SSD expects to bring its own controller, so it won't work. The storage is also tied to the chip's Secure Enclave.
How much does Apple charge for more storage?
In October 2026 on Apple's US store, going from 256 GB to 512 GB on a Mac mini added $200, 512 GB to 1 TB on a MacBook Air added $300, and 1 TB to 2 TB on a MacBook Pro added $500. Prices differ by country and change with new models.
Is an external SSD as good as internal storage?
For libraries, projects, games and archives, a fast external SSD on a Thunderbolt or USB 4 port works well. It's less convenient for a laptop you carry, and apps' everyday data should stay on the internal disk. Keep a backup: a single drive isn't one.
Does a third-party SSD upgrade void the Mac's warranty?
Apple's limited warranty doesn't cover damage caused by service, including upgrades, done by anyone other than Apple or an authorized provider, or a Mac modified without Apple's permission. Consumer law where you live may still give you rights.