Most people's backup strategy is either nonexistent or dangerously incomplete — a single external hard drive that hasn't been plugged in for six months, or cloud storage that covers photos but nothing else. A NAS changes this by becoming an always-on, always-connected backup target that your computers, phones, and tablets back up to automatically, every day, without any manual intervention.
The right backup NAS for home and small office use needs three things: reliable backup software that handles versioning and scheduling, broad compatibility with Mac Time Machine and Windows backup, and a path to offsite backup for the copy that lives outside your home. Synology's DSM software leads the field on all three counts, which is why Synology appears prominently in these recommendations — but QNAP and others are competitive for users who want alternatives.
Top Picks at a Glance
| Pick | Backup Software | Mac Time Machine | Windows Backup | Offsite Sync | Price |
|---|---|---|---|---|---|
| Synology DS224+ | Hyper Backup, rsync, Cloud Sync | Yes (SMB) | Yes (File History, SMB) | Backblaze B2, S3, Google Drive, more | ~$300 |
| Synology DS923+ | Hyper Backup, rsync, Cloud Sync | Yes (SMB) | Yes (File History, SMB) | Backblaze B2, S3, Google Drive, more | ~$600 |
| QNAP TS-264 | Hybrid Backup Sync | Yes (SMB) | Yes (File History, SMB) | Backblaze B2, S3, Google Drive, more | ~$350 |
| TerraMaster F2-424 | TOS Backup, rsync | Yes (SMB) | Yes (SMB) | rsync, cloud limited | ~$250 |
| UGREEN NASync DXP2800 | rsync, Veeam Agent | Yes (SMB) | Yes (Veeam, SMB) | rsync, cloud via containers | ~$280 |
Our Picks in Detail
- Hyper Backup, Time Machine, rsync, and cloud sync built in — the most complete backup NAS for home a
- Four-bay Synology with the same Hyper Backup ecosystem — more capacity for larger backup targets and
- Hybrid Backup Sync with strong cloud integration, Time Machine support, and dual 2
- Affordable Intel N95 hardware with improving TOS backup apps — a solid rsync workflow NAS at a compe
- Modern 2
Prices are for diskless enclosures. NAS-rated drives are sold separately and are a significant portion of the total cost.
The 3-2-1 Backup Rule: Why One Copy Is Never Enough
The 3-2-1 backup rule is the most widely accepted framework for data protection, and for good reason: it addresses the most common failure modes simultaneously. The rule is simple: keep three copies of your data, on two different types of media, with one copy stored offsite.
In a home context, this typically looks like: copy one is the original data on your computer's internal drive; copy two is the local backup on your NAS; copy three is an offsite backup in the cloud or on a drive stored at a different physical location. The two-media requirement ensures that a single failure event — a power surge, a fire, a ransomware attack — cannot take out both local copies at once. The offsite requirement ensures that a physical disaster at your home cannot destroy all your copies.
A NAS is the natural home for copy two. It sits on your network, backs up your computers automatically, stores multiple versions so you can recover accidentally deleted files, and serves as the staging point for sending copy three to the cloud. A NAS alone is not the complete solution — it is one-third of it — but without a NAS, most people never reliably implement copies two and three at all.
For small offices, the same logic applies at larger scale: a NAS backs up workstations and servers on the local network, while Hyper Backup or Hybrid Backup Sync pushes encrypted copies to cloud storage on a schedule. This gives you fast local restores for the common case (a user deleted an important file) and offsite recovery for the disaster case (the office burns down).
RAID Is Not a Backup: What RAID Protects Against and What It Doesn't
This point deserves its own section because it is the most common misconception about NAS backup. RAID — whether RAID 1 mirroring or RAID 5 parity — is a drive failure tolerance mechanism, not a backup. It is an important feature for keeping a NAS running after a drive fails, but it does not protect your data in most scenarios that actually cause data loss.
RAID 1 keeps two identical copies of your data across two drives. If one drive fails, the NAS keeps running on the surviving drive. This is valuable — it means a drive failure doesn't result in downtime or data loss and gives you time to replace the failed drive. What RAID does not protect against: accidental file deletion (deletes are mirrored instantly to both drives), ransomware (encryption propagates to all drives in real time), the NAS enclosure failing (both drives survive but may not be readable elsewhere), theft (an attacker takes both drives), fire or flood (destroys both drives simultaneously).
Run RAID 1 on your backup NAS — absolutely. It reduces the risk that a single drive failure takes your backup target offline at the worst possible moment. But run RAID in addition to proper backups, never instead of them.
Synology Hyper Backup: Setting Up Versioned Backup With Retention Policies
Hyper Backup is Synology's flagship backup application and one of the most capable backup tools available on any NAS platform. It backs up data from the NAS to external destinations — USB drives, rsync servers, or cloud storage — with full versioning, deduplication, and flexible retention policies.
The versioning model is particularly useful: Hyper Backup stores incremental snapshots on a configurable schedule, and you can configure how many versions to retain and how far back they go. A typical home policy might keep daily backups for 30 days, weekly backups for 6 months, and monthly backups for 2 years. This lets you recover a file you deleted a year ago, not just last week.
Deduplication means Hyper Backup is storage-efficient: if a file doesn't change between backup runs, only one copy is stored, with additional versions referencing it. This keeps offsite cloud storage costs manageable even with deep version history.
Critically: test your restores. A backup you have never tested is a backup of unknown reliability. Hyper Backup includes a restore integrity check function — run it monthly to verify your backup is readable. Actually restore a few files periodically to confirm the process works end to end.
Mac Time Machine and Windows Backup to a NAS
Every Synology, QNAP, and TerraMaster NAS supports Time Machine over SMB, making them drop-in Time Machine targets for Mac users. The setup process on Synology is straightforward: create a dedicated shared folder for Time Machine backups in DSM, enable it as a Time Machine destination (DSM has a dedicated toggle for this), and set a storage quota so Time Machine doesn't consume the entire volume. On the Mac side, open Time Machine preferences, click Add Backup Disk, and your NAS folder appears in the list.
One important detail: set a Time Machine quota on the NAS. Without a quota, Time Machine will eventually fill your entire NAS volume. A quota of 1.5–2x the Mac's internal storage capacity is usually appropriate, giving Time Machine room for multiple version snapshots while preserving space for other uses.
For Windows, File History is the built-in backup tool and works well with a NAS SMB share as the backup destination. Navigate to Settings > Update & Security > Backup, point it at a NAS network share, and Windows backs up your files on a schedule. Windows Server Backup and Veeam Agent for Windows (which has a free tier) offer more advanced options including full system image backups, useful for small offices that need bare-metal restore capability.
Offsite Backup from a NAS: Cloud Sync Options
The offsite copy is the one most people skip, and it is the one that matters most when disaster strikes. Synology Hyper Backup and QNAP Hybrid Backup Sync both support sending encrypted backups directly to cloud storage on a schedule, making offsite backup as close to automatic as possible.
Backblaze B2 is the most cost-effective option for most users at $0.006 per GB per month — 1 TB of offsite backup costs about $6/month, 5 TB costs $30/month. Amazon S3 is more expensive but widely supported. Google Drive and OneDrive are options if you already have storage there, though they cost more per GB than dedicated object storage.
Encryption before upload is essential. Both Hyper Backup and Hybrid Backup Sync encrypt data with your own key before it leaves your NAS. This means the cloud provider cannot read your files, and a breach of the cloud provider doesn't expose your data. Keep your encryption key stored safely somewhere other than the NAS itself — losing the key means losing access to your offsite backup.
For the initial upload of large data sets, be realistic about timing. A 1 TB initial backup upload over a 100 Mbps upload connection takes roughly 22 hours. A 5 TB initial upload takes 4–5 days. Plan to run the initial backup over several days in the background, then let incremental daily backups keep it current — incremental uploads of the day's changes are typically a few GB and complete overnight.
Frequently Asked Questions
Does a NAS replace cloud backup?
No. A NAS is the local component of a 3-2-1 backup strategy, not a replacement for offsite backup. A NAS and cloud backup are complementary: the NAS gives you fast local restores and versioning, while cloud backup protects against fire, flood, theft, and other physical disasters that could destroy both your computer and your NAS simultaneously.
Can I use a NAS as a Time Machine backup target?
Yes. Synology, QNAP, TerraMaster, and most NAS devices support Time Machine over SMB. Synology DSM makes Time Machine setup particularly easy — create a shared folder, enable it as a Time Machine destination in DSM, and the Mac finds it automatically in Time Machine preferences. Set a storage quota so Time Machine does not consume the entire NAS volume.
How much storage do I need for a backup NAS?
A good starting point is 2–3x the total size of the data you want to protect, to allow for multiple backup versions and retention history. If you are backing up a 1 TB laptop and a 500 GB desktop, plan for 3–5 TB of usable NAS storage. In a 2-bay RAID 1 configuration, that means two 4–6 TB drives.
What happens if my NAS dies and I have all my backups on it?
This is exactly why RAID alone is not a backup strategy, and why the 3-2-1 rule requires at least one copy offsite. If the NAS is destroyed by fire, flood, theft, or a power surge, all data on it is gone regardless of RAID configuration. Always keep at least one copy of your critical data somewhere physically separate from your NAS — a cloud service like Backblaze B2, an external drive stored at another location, or both.