If you don't have the budget for a new Mac, there are other ways you can give older Mac a boost. Extra memory is always useful if you haven't already filled the slots to the maximum, although the biggest enhancement will come with the addition of a solid-state drive (SSD), which Apple calls a Flash Drive across its current range.

Read next: Best NAS for Mac | Best Mac hard drives

There are also portable drives, which can be used as a primary or secondary drive for your Mac. Nowadays, most external portable drives come with flash drives, which use the same NAND flash technology as an SSD that you would install in a Mac system. Thus, SSD technology is used in both internal and external drives; just make sure you see the 'SSD' label on a product page, as there are still hard disks in the market.

If you're looking for our top SSD recommendations you can click here to jump straight to the products.

Also see: How to upgrade an old Mac - Create a FrankenMac!

Updated 23 August with general updates and new SSDs.

Best SSD for Mac: External vs portable SSD drives

Back when SSDs first launched, no one thought they would become affordable nor portable. Thankfully, they have through the use of NAND flash technology, where a micro-SD houses the same technology as a 2.5in internal SSD drive which goes inside a computer.

This is why you'll find external drives now sporting the SSD name. However, if both external and internal drives use flash technology (aka SSD), then surely a portable drive will always be the better option, as it's easier to transport?

It's a good assumption, however, internal drives have dedicated memory controllers which allow them to perform at impressive read/write speeds. Whereas, external drives are often limited by the bandwidth limitations found on a USB or Thunderbolt port, meaning their speeds are ultimately affected.

So, where possible try to aim for an internal SSD drive for the best possible speeds. If however, you're looking for something portable and easy-to-install, then a portable SSD will still give you a healthy performance boost over a traditional hard disk found in cheaper or older Macs.

Best SSD for Mac: Is my Mac compatible?

The first consideration is whether it’s even possible to upgrade your Mac this way, and if so with which SSD.

If you're buying an external SSD drive, you'll want to look for the type of port used. Most Macs have a USB or Thunderbolt connection, some have a USB-C type connector. External SSD drives also have a variety of connections, so you'll want to make sure they fit with your Mac.

If it's internal, the MacBook, Mac mini and iMacs can be given a new lease of life with an SSD to replace the internal hard disk. But the current MacBook Pro with Retina display and MacBook Air already have flash drives, as does the Mac Pro, and flash drives have also been CTO options on recent iMac and Mac mini models. These Macs have less need for an SSD, unless you wished to increase storage capacity to a larger capacity than that of the original drive.

In the case of the MacBook Pro with Retina display, the original 2012 model and the mildly refreshed version of early 2013 can potentially be upgraded, using third-party copies of Apple's proprietary mSATA-like drive.

Any MacBook Air up to the 2012 model can be similarly upgraded with a custom flash drive.

For MacBook notebooks made from 2013, Apple adopted a much faster version of SSD that it refers to as a PCIe-attached Flash Drive. While these can still be removed from the laptop, neither Apple nor any third-party vendor will sell you a replacement.

Macs that precede these will be using a SATA drive, and these can be brought up to and beyond modern speed with the addition of a solid-state drive inside. Popular candidates include MacBooks made from 2006 to 2012.

As for which type of SSD drive will work in your Mac, this isn't completely straightforward either. Almost every Intel-based Mac made since 2006 until recently had a Serial ATA drive – so any SATA SSD will work here. However, recent Macs rarely use this kind of storage. The first Air had a non-standard ZIF flash drive, then later, a removable flash card that resembled mSATA, but was proprietary to Apple.

And today of course, all current MacBook Pro models with a Retina display, the MacBook Air and the Mac Pro use removable PCIe-based flash. It has a connector that is unique to Apple. The new iMac straddles this divide, with either a SATA hard disk or PCIe flash drive; or both in the case of a Fusion drive. Excepting the near-extinct MacBook Pro (13-inch, Mid-2012), the only Mac currently on sale that will take a 2.5in SATA SSD is the Mac mini.

There are plenty of guide out there per Mac, for example OWC have a good variety of installation videos.

Read our round up of the best storage devices available now: Best storage options for Mac

Best SSD for Mac: OS X, TRIM and code signing

With the release of Yosemite, Apple has made it harder to enable TRIM support on third-party SSDs. But what is TRIM, and why should this matter?

TRIM is a system command that forces a drive to fully erase empty space in preparation for the next write. This can help keep the SSD perform at its fastest for write operations, since otherwise empty blocks – that is, areas of NAND flash with unwanted 'deleted' data still preserved – must be first pre-erased before they can be written to again. This slows down file write operations slightly, adding a little more latency, although given the high speed of flash it may not be noticeable to the user.

While all built-in SSDs in recent Macs can take advantage of this feature, Apple has never enabled the operating system to use TRIM for aftermarket drives from other vendors. There have been ways to force TRIM support, typically with shareware utilities that will carry warnings that the user takes on the risk associated with patching crucial kernel extensions (kexts).

With OS X 10.10 Yosemite (and newer versions) already include additional code signing of such kexts, a security measure to help reduce the chance of malware and hackers gaining control of the system. The side effect of this safety measure is that the former TRIM kext hacks will no longer work.

One solution to keep TRIM enabled with an upgrade SSD in Yosemite and El Capitan is to disable code signing. Unfortunately, this is an all-or-nothing procedure which will switch off all code signing, and not just that of the storage drive kexts.

The process can be executed with a few lines typed into the Terminal, which modifies the non-volatile RAM (NVRAM) of the system. The process will set your Yosemite-running Mac to a similar state of security as Mavericks and earlier versions of OS X.

But TRIM support is by no means essential. Most people running SSDs in their Mac will never have noticed its absence thanks to other protocols that automatically maintain drive performance. Such garbage collection routines move data and optimise flash cells without further user input or reliance on TRIM commands.

Best SSD for Mac: What to look for when buying an SSD

When buying an SSD, look out for long warranties and high data-write limits if you prize data integrity. Some SSDs demand more power than others, and where this is known, we’d advise against fitting in a MacBook if you value your time away from the mains.

Also look out for manufacturers that support Mac users by making firmware updates possible on the platform. Many storage brands are still firmly routed in the Wintel world and don’t make it easy for Mac users to apply essential maintenance patches that sometimes are made available to end users.

For older MacBook Pro models with a built-in CD/DVD drive you may be able to replace the optical drive with a custom adaptor into which you can install an SSD. This way you can keep the existing hard disk for bulk storage, and install the OS and applications on the faster SSD.

Best SSD for Mac: An SSD will transform your experience

Apple got it right with the first MacBook Air in 2008. As a very expensive optional extra, you could order an ultra-thin laptop with a novel solid-state storage drive inside.

Instead of a fragile magnetised disk whirring at 70 revolutions every second, binary data was stored in shockproof silicon chips. But besides being physically robust, silent, smaller and lighter than any hard-disk drive, the big incentive to go flash was sheer performance. Data can simply be read and written hundreds of times faster from electronic non-volatile memory.

And this speed factor is about far more than go-faster bragging rights, as we find when old-school desktop PCs battle it out over who has the fastest processor and hottest graphics card. It’s all about the user experience – applications launch in almost no time, web pages spawn faster, files copy in a fraction of the time.

Put simply, regardless of the processor numbers, the whole computer just responds incredibly quickly to your touch. The main drawback back then was the high price of this kind of premier-class luxury.

It’s taken six years or more, but we’re now at the state where the solid-state drive, the SSD, is a truly affordable component for anyone. If your budget won’t stretch to £1000, just juggle your storage budget instead and get a 256GB drive.

Performance has swelled in the intervening years too – not just in the drag-race test of copying big files, but with the way that small files can transfer. Most of the background housekeeping of a modern operating system, OS X no exception, is with the continual reading and writing of very small files of 4 kilobytes or smaller. It’s the random access of these that can choke older disks that need to move a pickup across several spinning platters.

We’ve reached a point where just about any SSD you put into a computer to replace a hard disk will transform your experience. For performance seekers like professional users, there’s still a case for finding the very fastest. And that fastest metric is still as much about small-file transfers, which we can measure by the number of input and output operations capable in one second – otherwise known as IOPS.

The best SATA flash drives are currently returning figures around 100,000 IOPS, made possible by the way that datastreams can be paralleled together, a major asset of using flash memory over hard disks. In this test we assess some of the SSD upgrade options.

Best SSD for Mac: Upgrade your Mac storage

Samsung 850 Evo

Samsung 850 Evo
  • RRP: £109.04

The Samsung 850 EVO is one of the best internal SSDs on the market. Using its V-NAND technology (vertical layering of the flash drive) it is able to deliver blistering fast speeds.

The drive is available in 120-, 250-, 500GB, 1- and 2TB storage capacities. When our sister publication PC Advisor reviewed the drive, it cost £109.04 for the 500GB drive. Prices do fluctuate, so make sure you look out for deals.

When benchmarked through CrystalDiskMark we found the internal SSD to perform very well, with sequential read speeds of 524.4MB/s and write speeds of 512.1MB/s. Its smaller 4K benchmark tests scored impressively with 36.3- read and 106.2MB/s write speeds.

The drive also features AES 256-bit encryption, making it more secure over some other SSDs on the market.

As this is an internal drive, you'll need to make sure it fits and connects to your Mac. The SSD consumes 4.7W when active and uses only 0.5W whilst being idle.

The drive comes with a five year warranty and has dimensions of 69.85x100x6.8mm.

The SSD is one of the most consistent and fastest drives found in the market today. Installing the internal SSD to an existing Mac system will add a lot of performance over a standard hard disk.

Toshiba Q300 (2016)

Toshiba Q300 (2016)
  • RRP: £79.99

The Toshiba Q300 (2016 version) is an impressive internal SSD, which is able to deliver fast speeds at a very affordable price. At the time of review, our sister publication PC Advisor reviewed the 480GB storage option at £79.99, making it one of the cheapest drives given its storage size.

The Toshiba Q300 (2016) comes in 120-, 240-, 480- and 960GB. The drive runs on Toshiba's very own 15nm triple-level cell (TLC) flash.

The drive also delivered impressive benchmark results, with its sequential performance hitting 529.3- read and 511.5MB/s write. Its 4K-performance was also performed well versus its competitors, with a read of 29.8- and write of 65.1MB/s.

The drive's dimensions are 69.85x100x7mm, where it consumes only 3.6W when active and 0.3W whilst idle.

Given its performance and price, the Toshiba Q300 (2016 version) is an inexpensive, fast-performance SSD that will deliver blistering speeds to any compatible Mac.

Buffalo MiniStation Thunderbolt

Buffalo MiniStation Thunderbolt
  • RRP: £237.98

Buffalo Technology's MiniStation Thunderbolt joins a shortlist of portable flash drives that accommodate both Thunderbolt and USB 3.0 connections. That adds welcome versatility, enabling connection to Windows PCs with their '5Gb/s' USB 3.0 ports, while Mac users can take advantage of the fastest desktop data bus in the business from '10Gb/s' Thunderbolt.

It weighs a little under 250g and is sized to accommodate an internal 2.5in SATA SSD. The result is not tiny at 130x81mm, and 24mm thick, but somehow its soft rounded bottom stamped from thin aluminium sheet, and frosted white plastic top, combine to make it rather preternaturally tactile. Inside is a 256GB Crucial M4 SSD.

Tested first over USB 3.0, the Buffalo averaged sequential reads at 401MB/s and provided write speeds far behind at just 258MB/s. While these speeds far exceed laptop disk drives they're also among the slowest we’ve measured for this capacity of portable flash drive. Turning to small-file transfer speeds from the Buffalo, data up to 1024kB averaged 155MB/s for random reads but just 66MB/s random writes.

Connected via Thunderbolt, the Buffalo drive's speed dropped to just 391MB/s sequential reads and the same 258MB/s sequential writes as USB 3.0. The small-file test reported random reads down at 146MB/s, and again 66MB/s for random writes.

The real flaw that still underlies Thunderbolt portable drives is underspecified supporting electronics, since power consumption available through the Thunderbolt bus is limited to less than that required with today's electronic components. This results in transfer speeds of portable Thunderbolt devices that lag behind the nominally slower USB 3.0 protocol.

The Buffalo's looks and tactility will recommend it to anyone taken by its neat form, but faster and cheaper USB 3.0-only portable drives offer better value.

Transcend StoreJet 500 Portable SSD

Transcend StoreJet 500 Portable SSD
  • RRP: £434.85

The Transcend StoreJet 500 offers both Thunderbolt and USB 3.0 connectivity, all finished in a smart all-aluminium enclosure that perfectly matches the natural metal finish of the Apple MacBook. At 121x75mm, and 12.5mm thick, it fits neatly into the hand, helped by nicely rounded corners. It feels solid yet weighs only 134g without cables.

On the drive's top is a small LED which lights blue to show connection, and blinks rapidly during transfers. And on the back edge are the two ports, Micro-USB 3.0 and Thunderbolt.  

Using the Thunderbolt connection, the StoreJet 500 was capable of 391MB/s reads and 291MB/s writes in large file sequential transfers. Those are speedy figures compared to hard disk drives that peak at around 100- to 120MB/s, but it also makes this Thunderbolt SSD much slower than the 500+MB/s that modern SATA Revision 3 solid-state drives deliver.

Small file reading and writing performance was good, with the average across 4- to 1024kB files amounting to 134MB/s random reads and 203MB/s random writes.

Turning to the USB 3.0 connection, the StoreJet 500 was capable of 437MB/s sequential reads and 297MB/s sequential writes. The read figure at least is on the edge of what is currently possible with USB 3.0 drives that are now employing the UASP protocol to overcome other limitations in USB 3.0 storage standard, but we would also expect to see sequential write speed closer to 400MB/S than 300MB/s.

Small-file transfers were at a similar level over USB 3.0 as they were with Thunderbolt; giving slightly faster than average for small random reads (144MB/s), and slightly slower than average for random writes (188MB/s).

Like other dual-connection flash drives before it, you’re better off sticking to USB 3.0, making the price premium demanded by such Thunderbolt SSDs a poor investment.

Adata SE730

Adata SE730

The Adata SE730 is an extremely impressive drive, which performs at blistering speeds whilst remaining affordable.

The drive comes in at £106.44 for a huge 256GB storage space. If that's not impressive enough, the SE730 has a weight of only 33g, 44x73x12mm size, IP68 certification, a USB 3.1 Gen 2 Type connector and houses the more reliable MLC NAND Flash SSD within its aluminium housing.

We benchmarked the SE730 and found it to be the most impressive portable drives we've ever come across, with an extremely impressive 380.8- read and 278.5MB/s write speeds in its sequential tests and 19.8- and 38.9MB/s in its smaller 4K file benchmarks.

The SE730 is an easy recommendation for those looking for a truly portable and super-sonic performance from a drive.

Samsung Portable SSD T3

Samsung Portable SSD T3
  • RRP: £606.06, US$710.82

The Samsung Portable SSD T3 is a portable storage drive little bigger than the mSATA card inside, and now with capacity to rival traditional laptop hard disks.

Many consumer gadget fans extol and elevate the virtue of being light in weight and possessing vanishingly small dimensions. And by that measure the Samsung T3 is a winner, measuring just 74x58mm, and 10mm thick. It's incredibly light too at just 51g.

The software on Mac demands you install an additional kernel extension to complete the unlock stage. This SCSI ATA Translation (SAT) SMART extension, despite the name, does not ultimately provide any readable SMART data for Samsung’s software. It really does look like an unnecessary hoop you must jump through, and an annoying extra kernel extension left widowed in the computer’s file system.

The Samsung Portable SSD.app software provides but one function, to access the drive’s AES 256 encryption. Once the T3 drive has been set up, it does not require any proprietary software to access the data.

Using CrystalDiskMark, we saw maximum sequential transfers of 406MB/s (reads) and 211MB/s (writes). Turning to smaller file speeds, 4kB reads and writes measured 21.9- and 2.3MB/s respectively.

The Samsung Portable SSD T3 1 TB is a fast and highly compact flash drive well suited to anyone that needs speedy storage without the noise and bulk of disk-based drives.

SanDisk Extreme 500 Portable SSD

SanDisk Extreme 500 Portable SSD
  • RRP: £70.02, US$92.99

SanDisk is best-known for its range of handy little memory sticks, but it occasionally branches out with other types of storage device, such as its Extreme 500. 

We're not entirely sure where the '500' comes from - although the largest version of the drive has 480GB of solid-state storage, so maybe they're just rounding up a bit. The 'Extreme' bit is self-explanatory, though, as the chunky drive is larger than most solid-state drives but designed to be shock-resistant and vibration-resistant, and to survive temperatures ranging from -4ºF to 158ºF. If you're after water-resistance, there is the much more expensive 480GB model, which comes with a red-edge.

It's still lighter and more compact than a conventional hard drive, though, measuring just 75.7mm square and 10.7mm thick, and a mere 78.9g in weight. It's also got a handy hook on one corner so that you can clip it onto a backpack or belt when you're hiking around the countryside.

We found the drive to perform very well with sequential speeds of 398- read and 203MB/s write speeds. For smaller 4K files it managed 19.8- reads and 3.7MB/s writes.

It's got a standard USB 3.0 interface, rather than the faster Thunderbolt, but that should still be fast enough for most users and, of course, ensures that the drive is compatible with older Macs and PCs that don’t have Thunderbolt.

The Extreme 500 is also pretty good value for a solid-state drive, starting at around £58.90 for a model with 128GB storage, £72.33 for 240GB, and a competitive £139.26 for the 480GB model. Note: Prices do fluctuate.

Transcend ESD400K SuperSpeed

Transcend ESD400K SuperSpeed
  • RRP: £408.10

Keeping up to 1000GB of data close to you is now a doddle - provided you can afford the £400-plus asking price. Transcend’s ESD400K goes up to 1TB size, yet still takes up next to no space and weighs just 56g. But the price of this technology in your pocket is currently around £408 for this capacity.

For smaller budgets and demands, you can also find it in sizes down to 128 GB, which costs around £49.99.
A suedette slip-on cover is included, a useful addition since the soft glossy plastic top can be easily scratched just by carrying in a bag with loose objects.

Like Samsung's T3, which follows the ESD400K and similar mSATA-based pocket flash drives, the low mass plasticky build actually makes the product too light to use confidently. Especially in this example where the cable weighs almost as much as the drive, and its intractable stiffness means the drive simply won’t lie straight anywhere on the desk.

Get past this minor annoyance, and you have a very speedy piece of storage in the palm of your hand. Like some other models in Transcend's drive range, the ESD400K includes a One-Touch backup button. Here, it’s so discreetly situated on one edge you could almost miss it. So if you have your own backup regime this superfluous addition shouldn’t even get in your way.

We measured speeds up to 433MB/s in OS X using QuickBench. Sequential write speeds were somewhat lower, perhaps even lower than we now expect with flash technology, but still decent at 370MB/s.

It’s almost too light but the ESD400K is also, just, the cheapest mSATA flash portable drive we’ve seen. For keeping a 1000GB in a tiny and lightweight plastic widget, it comes recommended.

SanDisk iXpand

SanDisk iXpand
  • RRP: £90

The iXpand has changed over the years, with the older variant of the flash drive bring a little chunky. The newer variant from SanDisk offers a unique design which is aimed to fit both in a USB 3.0 port and offer iPhone and iPad users additional storage through its lighting port connector.

Like most memory sticks the iXpand has a USB 3.0 interface for connecting to Macs and PCs and a Lightning interface for iOS devices. Through the iXpand drive app you'll be able to transfer photos and videos on to the iXpand in order to save space on your iOS devices.

It’s available with up to 128GB of storage, so it can handle even the largest video files that you may have on your iPhone or iPad. It also comes in 16-, 32- and 64GB variants.

The drive measures 59x17x13mm in size. You will need iOS 8.2 or above in order to use the device with your iPhone or iPad.

Freecom Tablet Mini SSD

Freecom Tablet Mini SSD

Memory sticks are cheap and easy to carry around, but they're generally not very fast. If you need a really portable storage device that provides better performance then Freecom’s pocket-sized mSSD is a great choice.

The mSSD measures just 9mm thick, 35mm wide and 80mm long, and weighs only 29g, so you can slip it into your pocket or into a case with your MacBook with no trouble at all. The aluminium casing looks nice and smart alongside your MacBook, and is sturdy enough to cope with a bit of rough treatment when you’re out and about.

The Freecom mSSD is a very lightweight portable drive. It has a metal case made from stamped aluminium with a brushed finish. The company name is printed on the top surface, and the capacity marked on one edge.

There is no protective carry case included, which is disappointing, especially since its sharp edges created scratches on other plastic items in our laptop bag’s pocket.

We tested the £83.99 128GB version - that's the same size as the SSD used in many MacBook models, so you can do a complete Time Machine backup and still carry it around in your pocket - and it's also available with 256GB. That bumps the price up to £199.99: still not bad compared to some of the other SSD drives currently available.

In sequential read speeds, the mSSD was found to measure at the limit of what's now possible from USB 3.0 drives, although its sequential write performance was much lower. In this case that’s probably because 128GB SSDs have slower write speed due to reduced parallelism compared to 256+GB solid-state drives.

Tested with 2- to 10MB files it averaged 439MB/s sequential reads and 148MB/s sequential writes. Small-file performance was good, if rather slower than the leading flash drives in this category. Random reads from 4- to 1024kB averaged 152MB/s while random writes averaged just 89MB/s.

The mSSD is a relatively inexpensive portable flash drive. It’s as quick as any other USB 3.0 flash drive when reading large files, but the 128GB option proved much slower at file writing. Nevertheless as a compact storage device, it will serve better than a regular USB thumbdrive.

It’s a shame that the mSSD only has a standard USB 3.0 interface, but Thunderbolt would add quite a bit to the cost, and USB 3.0 should still be fast enough for your routine Time Machine backups.

Kingston DataTraveler HyperX Predator

Kingston DataTraveler HyperX Predator
  • RRP: £225

Memory sticks probably seem a bit old-fashioned these days of cloud storage and solid-state drives, but there are still times when it's handy to copy a bunch of files onto a compact little stick and then just stick it into your jacket or trouser pocket. 

Kingston's HyperX Predator is actually quite bulky compared to most memory sticks, but that's because it's wrapped up in a tough, shock-resistant metal casing - zinc rather than the fashionable aluminium - and Kingston backs it up with a full five-year warranty to give you peace of mind when backing up your important data.

The drive uses a USB 3.1 interface, and Kingston also includes a small extension cable as the chunky Predator might not be able to squeeze in alongside cables for printers or other USB devices. The Predator also comes with a tough metal carrying case for extra protection, and a metal key-ring attachment so that you can keep it with you in your pocket.

The Predator comes in just two sizes, with 512GB priced (on Amazon at any rate) at a competitive £225, despite claiming that the RRP is a lofty £800. At time of writing Amazon is asking £588 for the 1TB version, set against a 'RRP' of £1,169.99, so it's clearly worth shopping around if you need that much storage. It weights 69g and measures 21x27x72mm.

Monster Digital Overdrive Mini

Monster Digital Overdrive Mini
  • RRP: £169.99

Monster is best known for its headphones and speakers, but the company also makes a number of storage accessories, including this compact little solid-state drive, which is very competitively priced following a recent price cut.

The Overdrive Mini is only slightly larger than a credit card, measuring 12mm thick, 53mm wide and 92mm long, and weighs just 63g so it's easy to slip into your pocket or into a case alongside your laptop when you're on the move. Despite its compact size, the Overdrive Mini provides plenty of storage for backing up your important files. It comes in 256-, 512GB and 1TB.

The stainless steel case looks nice and smart, and is also tough enough to provide good protection when you're out and about. The USB cable is separate, but there's a carrying pouch provided so that you can keep the drive and cable together when you're travelling.

The drive is supplied in the HFS+ format for Macs, so you can just plug it in and get started straight away, or just reformat it with Disk Utility if you want to use it with a PC instead. The Overdrive Mini uses a standard USB 3.0 interface, but that'll be fast enough for most people, and Monster also makes a Thunderbolt model as well, although that's quite a bit more expensive.