Everything most people know about deleted files comes from the era of spinning disks, where deleting removed the index entry and left the contents sitting patiently in place. Solid state storage broke that assumption completely, and the difference is not a matter of degree.
A hard disk writes over what was there. A flash cell cannot: it has to be erased before it can be written again, and erasure happens in large blocks rather than in the small pages the drive actually reads and writes. That mismatch is why an SSD has a controller doing a great deal of housekeeping behind the scenes, and it is why the drive maintains its own private map between the addresses your computer asks about and the physical cells holding the data.
The consequence is that the drive has to know which of its cells are still needed. If it does not, it ends up preserving data nobody wants, running out of pre-erased blocks and slowing to a crawl. So the operating system tells it, and the instruction that does the telling is TRIM.
When you delete a file on a modern system, the file system removes the index entry — the familiar part — and then issues a TRIM command naming the blocks that are now free. The drive marks them for erasure and its background garbage collection clears them, generally within minutes of the machine going idle. At that point the contents are not overwritten in the traditional sense. They are electrically gone, and reading those addresses returns zeroes.
On a solid state drive that is working normally, with TRIM active and no encryption complication, a deleted file is usually unrecoverable within minutes and certainly within hours. Not difficult. Not expensive. Not a matter of finding a better laboratory. The data has been electrically cleared from the cells by the drive's own housekeeping, and nothing reads back what is no longer there.
This applies to SATA SSDs, to NVMe blades, and to the soldered storage in most current laptops. It applies to an emptied recycle bin, to a shift-delete, and to a quick format on a volume the operating system knows about. It applies whether the drive is in a Windows machine, a Mac or a Linux box, because TRIM is universal now.
The reason this matters commercially is that it is not what anybody wants to hear, and there is a whole category of software marketed on the opposite promise. Recovery tools will happily scan a TRIMmed SSD for hours and produce a list of filenames read out of surviving metadata, most of which open as empty or corrupted. The filenames are real; the contents are not there behind them. Anybody who promises to undelete from a healthy modern SSD is either not aware of this or is relying on you not being.
Several circumstances mean TRIM never ran, and in every one of them the odds change completely.
The drive failed rather than the file being deleted. This is the important one and it is counter-intuitive: an SSD that has stopped responding, dropped to a fraction of its capacity, gone read-only or vanished from the BIOS is frequently a far better prospect than a working one. Nothing has been deleted, so nothing has been trimmed, and the whole of the data is generally still sitting in the flash behind a controller that has stopped cooperating. The work is getting past the controller rather than finding erased material.
TRIM was never passed through. External SSDs in USB enclosures historically did not pass TRIM commands through the bridge, and a good number still do not. The same applies to some RAID configurations, to older hardware controllers, and to drives connected to systems that never enabled it. In those cases an SSD behaves much more like a hard disk and deleted data can survive for a long time.
The file was overwritten rather than deleted. If a document was saved over rather than removed, earlier versions may exist in application temporary files, in shadow copies, or in the space the file grew out of, none of which are subject to TRIM in the same way.
You acted within minutes. Garbage collection runs when the drive is idle. If a machine was powered off within a minute or two of the deletion and has not been switched on since, some of the data may still be there. That is a genuine window and it closes fast, which is the argument for pulling the power immediately rather than carrying on and hoping.
If you have just deleted something from an SSD and it matters, shut the machine down now. Not sleep, not hibernate — off. Every minute of idle time is a minute the drive spends clearing exactly the blocks you want. This is the only action that improves your odds, and it improves them a great deal in the first hour.
Then stop. Do not install recovery software onto the same drive, which writes to it. Do not run a scan across it, which keeps it awake and busy. Do not defragment it — modern systems will not, but older configurations sometimes still try, and on flash it achieves nothing except wear. Do not let anything repair the volume.
And where the drive has failed rather than lost a file, the advice is the same and the reasoning is different. A failing SSD that still enumerates should be imaged rather than browsed. Copying files off it one folder at a time keeps it powered, warm and working, and the controller in a drive that is going wrong tends to get worse the longer it is asked to keep going.
Recovering a failed solid state drive is a different discipline from recovering a hard disk, and it is worth understanding what you are paying for. Where the controller still responds, the drive is imaged in the ordinary way, slowly, with timeouts set to suit a device that argues back. Where it does not respond at all, the flash has to be read directly — the chips addressed on their own terms rather than through the controller that is supposed to interpret them.
That second route is where the work is. The raw contents of a flash die are not your files in any useful sense. The controller applies its own scrambling, spreads consecutive data across multiple dies and planes, maintains error-correction codes and keeps a translation map that only it understands. All of that has to be reconstructed before a single readable file appears, and it varies by controller family and sometimes by firmware revision.
Two honest limits go with it. Reading chips directly is chip-level work, one of the stated exclusions from no fix, no fee, so it takes 50% upfront. And storage soldered flat to a mainboard — Apple Silicon Macs, many current ultrabooks — cannot be removed, so where the board itself has failed there is nothing to work on and the answer is no. Better said here than after somebody has paid for postage.
A single hard drive or SSD is £300 + VAT, with NVMe blades on the same rung, and that covers both a logical job and a failed drive. Memory cards, USB sticks and pen drives are £250 + VAT. A BitLocker or otherwise encrypted volume is £400 + VAT, as is a disk out of a CCTV or DVR recorder. Arrays and servers start at £500 + VAT. The diagnostic is free, closes 2 working days after booking in, and produces one fixed written figure. Logical faults run no fix, no fee; the stated exclusions are electronic and mechanical failures, chip level work, DVR and Forensic jobs, at 50% upfront.
Send the drive rather than the machine. An M.2 blade comes out with one screw, a 2.5-inch SSD with four, and nothing is dismantled at the Cambridge end. The exceptions are an external drive, which travels sealed in its own case, and a WD My Passport or My Book, which goes whole with its cable because the encryption key sits on the bridge board rather than on the disk. Pack it so nothing moves and post it tracked and insured to Cambridge Data Recovery, Compass House, Vision Park, Chivers Way, Cambridge CB24 9AD.
That is seventy miles from Leicester by road, M1 south to Junction 19 then the A14 east, and the lab is two minutes off Junction 32 with parking outside; reception takes drop-offs Mon–Fri 9:00am–5:30pm and nobody collects. The pages alongside this one are SSD data recovery, NVMe recovery, deleted file recovery for the spinning-disk version of the same question, and data recovery cost. The freephone is 0800 689 0668.
A failed SSD is often a better prospect than a working one. Nothing has been deleted, so nothing has been trimmed, and the data is generally still in the flash behind a controller that has stopped answering. The hopeless case is the opposite: a healthy drive, a deleted file, and a machine that has been left running.
Diagnosis costs nothing and finishes 2 working days from the moment Cambridge books your device in. The figure after that is written down and fixed. £250 + VAT a card or stick, £300 + VAT one drive or SSD.