Apple iMac Retina 4K, 21.5-inch, Late 2015 - 3.1GHz Core i5 Compatible Memory / RAM Upgrades

100% Apple Compatible Upgrades from the UK's Leading Supplier of Memory & SSDs

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Model Specifications 220,349 Apple Upgrades Supplied

Make & Model:	Apple iMac Retina 4K, 21.5-inch, Late 2015 - 3.1GHz Core i5
Apple Reference:	iMac16,2 2833 A1418 MK452B/A MK452LL/A
Installed Memory:	Non Upgradable
Model Guide:	Download User Guide for your Apple iMac
Important Notes:	For Guaranteed Compatible Memory, please choose a model that matches your model's Release Date, Screen Size and Processor. How to Identify your Apple.

Sorry, there are no Memory upgrades available for this model.

The manufacturer may have installed the maximum RAM or the RAM slots may be inaccessible.
It is also possible that the supported RAM type is no longer available.

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Google Reviews

Excellent and well laid out website, easily found my motherboard and the correct memory sticks for it. Prompt and well packaged delivery. PC now much faster.

John Fiore - Friday 12th June 2026

Purchase experience - very good. Memory modules delivered in good quality packaging. Installed and working perfectly. Cheers.

Jeff Daniels - Thursday 11th June 2026

I don't use Mr Memory frequently but have bought from them for many years when upgrading my (and extended friends and family's) various computers or replacing hard drives. I have never had cause to contact them outside of the normal process because a) everything has always been spot on and b) I haven't been a numpty before and ordered the wrong thing! So the most recent transaction with them has been a wholly enjoyable experience and totally different from any other contact I have had with any other company.
I ordered PC memory, when I should have ordered laptop memory -totally my fault! - and upon completing the returns details (which is all free post by the way!) I received an email from a wonderful person named Zoe, who happens to be Head of Operations, within 30 minutes giving me a return reference and asking what I wanted to exchange it for (the return request was for replacement not refund).
I replied with my brain fart issue and stated the laptop memory needed.
I received a very fast reply stating the laptop memory will not be in stock until the following Monday.
I then - being the awkward customer I am - asked if it could be posted to a different address as I was on a bit of a time crunch. Zoe replied saying it wouldn't be a problem. I then asked how I could pay the (very small amount) difference..... and she replied saying that they wouldn't charge any more than I had already paid!
If anyone out there doesn't agree about the absolute first class customer focus and service after hearing all my issues and stupidity that Zoe dealt with....
I have no words!
Thank you Zoe and Mr Memory, I am very glad I purchase hardware from you and will continue to do so!

Helen Saunders-Pederick - Friday 24th April 2026

Rated 4.8 out of 5 on Google MORE REVIEWS