Synology has been the default recommendation for a home NAS for well over a decade, and for a UK household already running Home Assistant, it solves a specific problem: local, reliable storage that does not depend on a cloud subscription. This review covers three current DiskStation models spanning the price range, the DSM software that makes Synology worth the premium over a bare drive enclosure, and how it compares with a DIY Raspberry Pi NAS build.
Why a smart-home household would want a Synology NAS
Home Assistant itself does not need much storage to run, but the things around it add up quickly. Local backups of your Home Assistant snapshots mean a failed SD card or SSD on your HA host does not wipe months of automations. A NAS also gives you somewhere to store the growing recorder and history database if you move it off the HA host itself, a dedicated Frigate NVR footage archive if you are running local camera detection, and a family photo and video library via Synology Photos instead of paying for iCloud or Google One storage every month.
The other reason Synology specifically comes up in smart-home circles is DSM, Synology's own operating system. It runs entirely in a browser, needs no command-line knowledge for day-to-day use, and includes a Container Manager package for running Docker containers — which is how many home-lab users run Frigate, a Home Assistant instance, or other self-hosted tools alongside their file storage on the same box.
DS225+, DS425+ and DS925+: three price tiers compared
Synology's current DiskStation line-up spans well beyond these three, but these models represent a sensible budget-to-prosumer spread for a home smart-home setup.
DS225+ (entry, 2-bay): two drive bays, an Intel Celeron J4125 quad-core CPU, and 2GB of non-ECC DDR4 RAM as standard, expandable to 6GB via a single additional SODIMM module. It is the cheapest sensible entry point into DSM and suits backups, file sharing and a modest photo library, though its CPU and RAM ceiling limit how much you can ask of it beyond that.
DS425+ (mid-range, 4-bay): four drive bays plus two M.2 2280 NVMe slots for SSD caching, the same Celeron J4125 CPU as the DS225+, and 2GB of RAM expandable to 6GB. The extra bays give more raw capacity and room for RAID redundancy across four drives rather than two, at a moderate step up in price.
DS925+ (prosumer, 4-bay): four drive bays, an AMD Ryzen V1500B quad-core CPU, and 4GB of DDR4 ECC SODIMM RAM as standard — expandable to 32GB across two slots. It is the most capable of the three for running Container Manager workloads such as Frigate or a self-hosted Home Assistant alongside file storage, and its ECC memory is a meaningful reliability upgrade for a box that is meant to run unattended for years. It replaces the previous-generation DS923+, which used a similar Ryzen platform but with 1GbE ports and a PCIe 10GbE upgrade slot the DS925+ drops in favour of built-in 2.5GbE.
UK street prices for these three sit roughly in the £350, £550–£600 and £650 ranges respectively for the diskless enclosure — prices vary by retailer and do not include drives, which typically add another £150–£400 depending on capacity and whether you choose NAS-rated drives such as Seagate IronWolf or WD Red.
DSM software: what you actually get for the premium
Synology Photos replaces the older Moments app and handles automatic backup and facial/object recognition for phone photos and videos, functioning as a private alternative to Google Photos or iCloud. Hyper Backup lets you schedule versioned backups of the NAS itself to an external drive, another Synology unit, or a cloud target, which matters if you are storing anything irreplaceable such as Home Assistant configuration history or a camera footage archive. Container Manager (Synology's rebrand of its Docker package) is the piece that turns a Synology box from “just storage” into a small home-lab server capable of running Frigate NVR, a secondary Home Assistant instance, or other self-hosted containers alongside your files — though CPU and RAM headroom on the entry-level Celeron models will limit how much you can comfortably run at once.
Synology vs a DIY Raspberry Pi NAS
A dedicated Synology box is not the only route to home NAS storage. Our Raspberry Pi NAS UK guide covers building an OpenMediaVault-based NAS on a Raspberry Pi 5 for roughly £150–160 all-in, excluding drives — meaningfully cheaper than any of the three Synology models here, and a genuinely capable option if file sharing and basic backups are all you need. What you give up versus Synology is DSM's polish: Synology Photos, Hyper Backup, and Container Manager are considerably more turnkey than assembling the equivalent stack yourself on a Pi, and Synology's RAID/SHR tooling and drive-failure alerting are more mature than OpenMediaVault's. If budget is tight and you are comfortable with some light Linux administration, the Pi route is worth serious consideration first.
For a broader comparison across brands and budgets, our best NAS for home UK roundup covers Synology alongside QNAP and other options at each price point.
Verdict
For a UK smart-home household that wants local Home Assistant backups, a private photo library, and the option to run Frigate or other containers alongside file storage, Synology's DSM ecosystem is still the most polished option on the market. The DS225+ is a sensible low-cost entry point if you mainly need backup and file sharing; the DS425+ adds bays and NVMe caching for a modest price step; the DS925+ is the one to pick if you intend to run Container Manager workloads seriously, thanks to its Ryzen CPU and ECC RAM headroom. Whichever tier you choose, budget separately for NAS-rated drives, and treat Hyper Backup as essential rather than optional if the NAS is your only copy of anything important.
