Make Photos for OS X shine — add photos by importing your iPhoto library.
Photos for OS X makes it easy for you to import your iPhoto Library into the app. If you just have a single iPhoto Library, Photos will do the work automatically for you. If you have multiple libraries, you'll have to choose which one you want to import. Here's how.
If you have a single iPhoto Library

If you're upgrading to Photos for OS X from iPhoto and you've only ever had a single iPhoto library on your Mac, your upgrade path is easy: After you open the app for the first time, Photos will automatically import all your iPhoto images into the app.
Your old iPhoto library will still remain if you need to use iPhoto for whatever reason, but changes made to those older images won't automatically sync to your new Photos library. If you don't need your old iPhoto library, you can toss it in the trash — your images are now safely in Photos (and, if you've turned on iCloud Photo Library, in iCloud as well).
If you're working with multiple libraries
Photos for OS X is only compatible with one primary library per Mac: This means that you can't combine multiple old iPhoto or Aperture libraries into one master library. (Aperture does have this capability, if you need to merge some libraries; you can follow our how-to guide for more information on that front.)

As such, if you have multiple libraries on your machine, Photos will ask you to select which library you'd like to import when you first launch the app. Once you've selected the library you want to use, Photos will prep and import those images.
You can still upgrade your other older libraries to separate Photos libraries; you'll just have to individually import each one by option-clicking the Photos icon when starting the app. This brings up the "Choose Library" screen, where you can select a current Photos library or an older iPhoto or Aperture library to import.

These other Photos libraries function identically to each other, with one exception: Only one library can be synced with iCloud Photo Library at a time. Your others will be locally (or externally, if you have them on a hard drive) siloed from iCloud's sync service.
Reader comments
How to import your iPhoto Library into Photos for OS X
Is there any recommended way to merge existing iPhoto libraries before updated to the new Photos (or after the fact).
Check out How to import multiple libraries into Photos for OS X
So the answer is "get Aperture?"
If you want to merge libraries, yep. Otherwise, I suggest importing one library, exporting photos in full resolution from your other libraries, and importing those as folders. There's a third option involving swapping your iCloud designation on multiple computers to upload everything to iCloud and then pull it back down, but I highly don't recommend it.
You could use iPhoto Library Manager to merge libraries before importing them. I've enjoyed using this. http://www.fatcatsoftware.com/iplm/
I'm going to answer my own question... Macworld (http://www.macworld.com/article/2910321/automator-actions-geotagging-and...) suggests repeatedly using iCloud storage and repeated importing each iCloud library into photos.
Is it possible to import the iPhoto library later, or a second time? I would like to try it out before committing to a change.
Yup! What I'd suggest is that you export one album or two from iPhoto, then make a blank Photos library and import those items. If you decide you want to keep using Photos, make a new Photos library from your entire iPhoto library.
You can hold the Option key while opening Photos to bring up a prompt to select an iPhoto/Aperture library to import from.
I have a big iPhoto library (almost 100GB), and I have 10GB storage left. Can I migrate it to Photos without having to move the entire library to external drive? I want to get rid of iPhoto as well.
Yep! This https://support.apple.com/en-us/HT204476 document's phrasing is a little odd, but essentially you won't be taking double the space when you migrate, even though it might look like it from an Info window. You should be able to do it even with 10GB left.
Serenity, you just wrote that you can delete the old iPhoto library after the conversion. But that conflicts with your statement above. As far as i understand the documentation from the Apple website, the migration creates symbolic links to the original photo in the iPhoto library. So if you delete the iPhoto library, you also delete all your master photos. Am i missing something?
Yeah, Apple's document is phrased poorly. The deal is: When you import your iPhoto library, all your masters etc are transferred to your new Photos library. Links are created in your old iPhoto library so that you can still work with those images, but when you delete the iPhoto library, all you're doing are deleting aliases, not the masters. Does that make sense?
It is indeed phrased poorly. It can be interpreted in so many different ways. But I will try it out later today.
Yep, it's actually make sense, because both old and new photolibrary show the (almost) same size which is normally imposible because it exceeds my drive size. I think the iPhoto library is designed to be deleted without harm, but I'm not sure about the way around. But thank you anw, and Photos is really awesome.
This means it's using hard links and not soft links (what you call symbolic links). Soft links take up almost no space at all and if you delete the original, the soft link or alias points to nothing.
With hard links, each instance of the file points to the same real data and shows the full size when getting Info. This is also how Time Machine works. Each backup will show the full size of the data it backed up, even if only 1 small file has changed. That's because the rest are hard links to the same files from the previous backup.
With hard links, when you delete an instance, as long as there's another instance still alive, the data will not really be erased. Only when the last instance is deleted will the actual data be removed.
I don't know how you are doing it but my iPhoto library which is about 110 GB and resides on an external Time Capsule, which has about 200 GB space available and I have tried 4 times to migrate and I keep getting a message that says Photos need an additional 185 GB to complete the setup.
Other than going out and buying a new 4GB external drive, is there something I am missing?
My iPhoto library was inside my internal HDD (in the Picture folder), so the migration was painless. I guess because your system partition in your internal HDD doesn't have enough space, so Photos app can't import you iPhoto library. I think you could create a new Photos library in your external HDD then import your latest version of your iPhoto library
Sure, that makes sense but if you read all the press, including Apple's and Serenity's posts, no additional space is required...so wherever your original library resides, the migration process does not duplicate (double the size) the library...in fact Apple claims it reduces the size of the library, and therefore does not require additional equipment to migrate to Photos...
yeah, I see the problem now. But to make it clear, Photos won't duplicate the library only if both old and new library locate in the same partition, thank for the hardlink that someone have mentioned above. But if they are locate on diferent HDD, I'm not sure... And the required space is weird too...
I guess the big question that exists at the tail end of this piece is: can I delete my original iPhoto library once the new Photos library has been generated? The two together take up almost my entire hard drive (both my original iPhoto Library and the new Photos library each measure 455 GB). I understand there's some new fancy method of file storage being used with this new app, which is too convoluted for my little mind, so it's totally unclear if I can delete my old iPhoto Library to save space, or if I can safely turf it now that I've migrated to Photos.
You can absolutely delete it, no harm.
Any recommendations about how to move an old iPhoto Libarary from and old iMac running Lion to Photos on a brand new MacBook Pro?
I'd use either an external drive or Dropbox (if you have a paid plan) to move your library to your new Mac.
Anyway to trigger the import? I've doen an upgrade on several machines and fired up Photos ... but no import library options appears.
You need to start Photos holding the option key.
I did the import from iPhoto last night, but my photo counts don’t add up, which concerns me. IT’s really hard to say how many it’s actually off, because comparing different views gives slightly different discrepancies, but it appears there are overall 560+ less photos in photos.app after the import than iPhoto is showing.
I have not connected iCloud Photo Library yet - I wanted to get my old iPhoto Library migrated first, and then mingle in the photos in the cloud (starting with 2015) after. I do know that on my iCloud Photo Library, the three different devices I view those on give different counts, even though I KNOW those should be the same - is Apple just having a hard time learning to count with their new apps?
Is this something others have experienced with iPhoto imports?
My guess (because I haven't jumped off the cliff yet!) is it doesn't import anything in your "trash" or "recovered" folders (?) If you're anything like me, you probably have that many photos in there =)
How can I import an iPhoto library that is on an external hard drive? I don't have enough storage for it on my built in drive and Photos doesn't see it.
I had this same issue, and I've resolved it—sort of. I followed the instructions at this Apple discussion forum thread.
https://discussions.apple.com/thread/6989035
I say "sort of" because this put my new Photos library on the external drive, and what I wanted to happen was to use the OPTIMIZE MAC STORAGE option and have the Photos library now on my 128GB MacBook Pro's drive.
So: Does anyone know how I can safely move my photo library, which is 200GB+, onto my 128GB MacBook Pro with that OPTIMIZE MAC STORAGE option? Clearly Apple has designed that option for people just like me -- and many others -- who have big photo libraries AND have a MacBook Air or MacBook Pro that can't accommodate all the photos/videos.
That's great for people who are just building a photo library, but what about all of us Mac users who have already been cobbling together solutions with iPhoto on external drives and now want our Photos library off of those external drives?
Thanks for the article Serenity. As far as merging iPhoto libraries - what about FatCat's iPhoto Library Manager? It has the ability to merge multiple iPhoto libraries. I have an older version, and multiple libraries that I am putting some thought and planning into how I'm going to move to Photos. But, you shouldn't need to go to Aperature from iPhoto just for the purpose of merging iPhoto Libraries if you go this route, is my thought (?)
Hi
One thing is totally unclear to me! How´s the synchronization for iCloud working?
It´s also written that only 1 Library at one time can be synched with the iCloud Library! That makes sense to me
BUT Is it always be the Standard-Library(System-Library) or is there a way to choose a specific Library I want to Sync with iCloud?
If I disable the synchronization with iCloud it tells me that photos are deleted and there are 30 days left to download the original file.
I assume that photos are also synched back to my photos app on my iMac. Does this deactivation of iCloud Synch then also affect this iMacs Library? Doesn´t make sense to me.
What if reached the limit of the iCloud storage.
If I delete photos from iCloud they will be deleted on all devices? But hopefully not in my Photos App on the iMac?
Quick question regarding Apple's future support for iPhoto: do you know for how long we'd be able to use Apple print services (photos, books, etc) within iPhoto, before I'd have to switch to Photos?
BTW, great MBW today!
After I uploaded to Photos, I took my pictures in iPhoto Events and made each event into an albums in Photos so I could continue to organize my pictures and make new albums with my new pictures. Then Photos randomly shut down and when I opened it back up all my pictures that I originally had in iPhoto Events were gone. All the albums were still there but no pictures in them and the pictures aren't under All Photos either. How else can I access these photos? Would they be stored anywhere on my hard drive at all?
what happened to the titles of my photos - when i transferred iPhoto to photo the titles of the pictures did not transfer
I have imported my if library, along with albums i have created. They are all appearing in Photos on my iMac but not on my iPad Air. Is there a way to make Photos on my iPad the same as photos on my iMac? Thanks
Ops.I have imported my iPhoto library.
Hey all, Do you know about one the stupidest mistakes I ever made? I buyed a Macbook and opened Photos, started to use it right away. My iPhoto library for my Mac is the one I should have imported this first time. It's the one that needs to become the one and only library for all my photos. Do you know how to make it so that Photos will act like a new-born so that I can finally import my iPhoto library as the basis of my future iCloud photo library? I'll send you chocolate and flowers if you could help me. Or whatever. But please please please help me.
You start Photos up with the Option key held down, then select your chosen iPhoto library.
Forgot to press the button to notify me. Still praying for your help.
When I connect my iPhone my photos are still automatically downloading into iPhoto. How do I now get those pictures into my Photos?
An easy way to merge libraries is to use iCloud Photo Lib. It will retain all metadata, etc. There is no way to do this with iPhoto unless you buy 3rd party software to do so.
Hello ! I made the mistake of clicking on "Create a new Library" the first time I opened iPhoto on my new laptop. It's extremely important I have the option to go back if possible ; my previous laptop got stolen mid-semester, and I think I had all my classroom blackboard pics in that library (although I didn't find them on my external drive from which I transferred all the data from my previous laptop). I'd like to try, at least, because it was a library from last November, strangely, whereas the last general backup I did on my external drive shows pics from August 15, latest.
Is there a way I can be asked that first-opening-of-iPhoto question again ? Thanks !