Mac Os X 10.6 Direct Download Link Updated

Question

Every yr / release this answer on installing previous versions of macOS will need updating.

Now the Apple has startup keys to assist recovery select multiple versions and official knowledge manufactures, it might be simpler to first check Apple's ain page on How to get old versions of macOS (which didn't exist when this Q&A started out), & come dorsum here if you withal take issues.

One thing that still applies throughout is - you need a Mac to become macOS easily & legitimately.

If you are trying to spring a long mode - say from 10.8 to 10.xiv or subsequently, received wisdom is to commencement upgrade to El Capitan 10.11, and then High Sierra 10.thirteen.
This will fix your machine for the long spring.
Some users seem to have managed to miss out El Capitan, but High Sierra withal seems necessary.

Since Mojave

[This section is withal work in progress]
It would appear that in the new Mojave App Store, older purchased Os Installers no longer announced at all, so the 'elementary method' of grabbing it from your purchase history is no longer valid.

Sierra, High Sierra & Mojave are available via direct links - meet beneath.

Testing the El Capitan installer which has a published URL it will appear in the App Store, but if requested to download no longer says 'not valid for this Mac' it now says 'The requested version of macOS is not available'.

Some further testing is required - contributions welcome - to run across if other OS versions are similarly removed. We may need directly links for these, which I don't take now.

Additional note:-
I've attempted from VMs of older OSes to recreate the App Store every bit it used to be in El Capitan & High Sierra, to see if I could nonetheless access the old 'purchase history'.. with no success. The history appears equally it used to, only I have been unable to admission any older versions through it.
Information technology seems you really demand a physical Mac running those older OSes to be able to reach back for those older versions.

For macOS versions since Sierra.

Sierra itself has now vanished from everybody's Purchase History. However, Apple are keeping Sierra fully bachelor, even though Loftier Sierra is out. No Apple ID is required.

Apparently, yous must utilize Safari to access these links, otherwise it doesn't correctly redirect to the App Shop.

High Sierra link tested from Mojave January 2019 - still works to download, though it does it via the new Software Update control console. It won't run on a Mojave Mac simply you lot have the installer in your Apps folder to movement elsewhere

For Os X versions from Lion upward to El Capitan.

I successfully re-tested this method Jan 2019 - still working as stated for a Mac limited to El Capitan. Purchased older OSes are still listed & attainable

The simplest way - if bachelor to you - is to employ your Purchase History on the App Store.
If you have ever previously installed any OS Ten version, information technology will even so exist available to y'all from that list. This should include any public beta versions as well.

The version available from that list will always be the latest version of its blazon - i.e. 10.7.5, ten.8.6... 10.11.6

^{Paradigm heavily modified to evidence simply OS versions.}

Note, it will say Download or Install depending on whether or not you have the Installer file saved locally - fifty-fifty on a non-kick bulldoze.

If the version you are trying to download is older than the Mac you are attempting to download it to - the Shop will not allow the download.
[looking for workarounds to this part - edits welcome - I tin can't test this as the newest Mac I have is a 2012 Mac Pro]

Potential workarounds, need testing -
How to re-download Panthera leo from Mountain Lion

For older Macs

If you lot are trying to update an older machine running Snow Leopard or King of beasts, then you tin can get a special version of El Capitan from the App Store

This version of El Capitan is for users running OS Ten Snow Leopard or Bone Ten Lion who would like to upgrade to macOS High Sierra. If you lot are running Snowfall Leopard or Lion and would similar to upgrade to High Sierra, you need to install El Capitan commencement. This version of El Capitan tin can also be installed on computers that are non compatible with High Sierra.

Note that last judgement... this version volition non install on any machine that is not currently on Snow Leopard or Lion, if the car is capable of running Loftier Sierra.
That leaves information technology as quite a specific resource & not a general 'go out of jail free card' for anyone wanting El Capitan.

Update July 2021

Apple accept removed the buy price from Panthera leo & Mountain Lion & made them free to download.

Mac Os X Lion 10.7
Mac Bone 10 Mountain Lion 10.8

Recovery Options

If you need to reinstall from Recovery, & were previously running Sierra 10.12.4 or higher, in that location are now 3 options available.
Hold the appropriate primal combo at the kick chimes...

Cmd ⌘ R
reinstall the latest macOS that was installed on your Mac, without upgrading to a later version
Opt ⌥ Cmd ⌘ R
upgrade to the latest macOS that is compatible with your Mac
Shift ⇧ Opt ⌥ Cmd ⌘ R
reinstall the macOS that came with your Mac, or the version nearest to it that is yet available.

The beginning 2 options are bachelor to any Mac newer than Panthera leo, approximately 2009.

Should you accept access to an older point release of any Bone, 10.eleven.0 etc & wish to upgrade, so you can download Combo Updaters from Apple that comprise everything necessary to go direct to the latest point release in a single pace, e.g. 10.eleven.6

Google is good at finding these, as the acme striking if you simply search philharmonic update x.11 etc but hither are links to a few

Mavericks x.9.v
Yosemite 10.10.5
El Capitan 10.11.half dozen
Sierra 10.12.6
High Sierra 10.13.half dozen
Mojave 10.14.six
Catalina 10.fifteen.7

Apple appear to accept abandoned the combo updater idea with Big Sur.

If you need to create a bootable USB to install from

How do I create El Capitan installer on a Catalina (or post-El Capitan) installed Mac for apply on USB boot installer?

How do I make a bootable USB OS 10 installer on a Mac?

How practice I create a Mac bootable USB drive using Windows?

If none of these methods are bachelor to you lot, you take two options

Discover a friend who can admission the download [recommended]
Detect a torrent/sharing site [not recommended]

Additional Annotation:
In that location is no 'legitimate' way to download macOS from anything other than a Mac. It requires the Apple App shop.

Annotation: You can non utilise a Time Automobile fill-in to revert to an OS which is older than the Os of the latest backup on that Time Machine drive.

This means that to preserve your ability to always restore to an earlier backup & Bone with your Time Machine fill-in, you lot must bandy out that Time Automobile drive earlier upgrading the Os. This is because once the Time Auto bulldoze sees the new Os, in that location'south no going dorsum to the older OS using it. You tin can still pick data out from the Time Machine manually, but cannot employ information technology to restore to the older OS.

I've moved this section to the bottom, simply to proceed for historical purposes.
This certificate issue should now be resolved.
NEWS
October 2019
Because of the certificate issue Apple faced, which overnight obsoleted all the previous macOS installers, they accept re-released several of these, with new certificates.

Apple tree KB - If an installer says it can't exist verified or was signed with a document that has expired
This contains links to further KBs for each of the half-dozen most recent OSes from Catalina back to Yosemite.
The three newer ones link to the App Store, only Sierra, El Capitan & Yosemite link to directly downloads.

Caution: Utilize Safari if your browser doesn't open the Mac App Shop links in the App Store app. iTunes and Music and iBooks and other apps tin't download these installers - they will say item not available, frequently quoting your state shop past name.

Note for those of us who like to continue all these for 'just in example'.
Download them one at a time & characterization them correctly earlier downloading another, then you know which is which. They are not identifiable from the dmg or installer proper noun as to which OS they are :\
Worse… even when yous run it, you get absolutely no indication of which OS it is going to install. Be careful.

The post-obit would probably still apply if you were trying to access something older than Yosemite…

General Note
This job seems to exist getting harder as time passes. A new contraction is that a lot of these older installers, fifty-fifty if you lot tin go hold of them, accept an 'expiry engagement'. The terminal widespread expiration appointment for many Mac installers was October 24, 2019 so you will demand to re-download your installers after that date to keep them valid and signed.

If yous encounter a message such every bit
"This copy of the Install OS X El Capitan application can't be verified. It may have been corrupted or tampered with during downloading",
or a more vague "An error occurred while preparing the installation. Effort running again"
A new mistake seems to be…
No packages were eligible for install.

Try setting your clock to a engagement within a year of the OS'south initial release engagement if you absolutely cannot re-download them.

From Michael Tsai'south blog - Installing Old Versions of macOS

Information technology seems that the installer is signed with a document that has expired. When booted from the installer, you can open Terminal and employ the engagement command to set the clock to the past, i.eastward. to when that version of macOS was current. Afterwards installing, be sure to fix the clock to the right date, or various other things won't work properly.

Mac Os X 10.6 Direct Download Link Updated