Offsite Backup for Homelab: S3 vs Backblaze B2 vs Cloudflare R2 Compared

Local backups protect you from disk failure. They do not protect you from fire, flood, theft, or ransomware that encrypts every attached drive. Offsite backup is the missing layer in most homelab setups, and it is easier to implement than you think.

This guide compares three practical offsite backup options for Linux homelabs: Amazon S3, Backblaze B2, and Cloudflare R2. The goal is not to recommend one provider. The goal is to show how each fits into a backup strategy using tools you already run, like Restic, Borg, or Kopia.

Why Offsite Backup Matters

The 3-2-1 backup rule is simple: three copies of your data, two on different media, one offsite. Most homelab users stop at two copies: the primary data and a local backup drive. That is not enough if the backup drive sits in the same room as the server.

Offsite backup does not have to mean enterprise tape libraries. A cheap object storage bucket with versioning and lifecycle rules can serve the same purpose for homelab-scale data.

Amazon S3

Amazon S3 is the most mature object storage service. It offers lifecycle policies, versioning, cross-region replication, and deep integration with backup tools. Restic, Borg, and Kopia all support S3 natively.

S3 pricing varies by region and storage class. The Standard class is expensive for active backup use, but S3 Infrequent Access and S3 Glacier Flexible Retrieval bring costs down for data you rarely restore. The downside is complexity. S3 has hundreds of features, and pricing can surprise you with egress fees, API request charges, and cross-region transfer costs.

Use S3 if you already use AWS for other services, need fine-grained lifecycle control, or want the strongest ecosystem support.

Backblaze B2

Backblaze B2 is designed as a low-cost alternative to S3. It offers S3-compatible API, simple pricing, and no egress fees when paired with Cloudflare. Restic, Borg, and Kopia work with B2 without extra plugins.

Pricing is straightforward: a flat per-GB storage fee and a flat per-GB download fee. There are no complex storage classes. The web interface is minimal but functional. The main limitation is fewer advanced features than S3. There is no built-in cross-region replication, and lifecycle rules are simpler.

Use B2 if you want predictable pricing, easy integration, and a service focused on backup and archive use cases.

Cloudflare R2

Cloudflare R2 is the newest entrant. It offers zero egress fees, S3-compatible API, and deep integration with Cloudflare Workers. If you already use Cloudflare for DNS or CDN, R2 fits naturally into your stack.

R2 pricing is flat: you pay for storage and operations. There are no bandwidth charges. The trade-off is maturity. R2 lacks lifecycle rules, cross-region replication, and some advanced S3 features. Not all backup tools support R2 perfectly yet, although Restic and Kopia work well.

Use R2 if you want zero egress costs, use Cloudflare, and can accept a simpler feature set.

Tool Compatibility

Restic supports all three providers with the same restic backup command. The only difference is the repository URL and credentials. Borg supports S3 and B2 through borg serve or borgmatic with S3 backends. Kopia has native S3 support and community B2 support.

If you use Proxmox Backup Server, you can export backups to any of these providers with proxmox-backup-client and a local staging directory, or use an intermediate backup tool like Restic to push data from the server to object storage.

Cost Comparison

Provider	Storage Cost (per GB/month)	Egress	Lifecycle Rules	S3 Compatible
Amazon S3 Standard	~$0.023	Paid	Advanced	Yes
Amazon S3 IA	~$0.0125	Paid	Advanced	Yes
Backblaze B2	~$0.005	Paid	Basic	Yes
Cloudflare R2	~$0.015	Free	Limited	Yes

Encryption and Security

Never send unencrypted data to object storage. Restic, Borg, and Kopia encrypt data before it leaves your server. The provider never sees your plaintext data. Use a strong passphrase and store it offline or in a password manager.

Enable versioning on the bucket. If a backup is corrupted or deleted locally, you can restore an older version from object storage.

Automation Strategy

Schedule backups with cron or systemd timers. Restic forgets old snapshots automatically with restic forget. Borgmatic can prune old archives. Kopia has built-in retention policies.

Run backups over a VPN or encrypted tunnel if you expose your homelab to the internet. Otherwise, push backups from your home network over your ISP connection. Most providers offer enough throughput for homelab-scale data.

Final Thoughts

Offsite backup does not have to be expensive or complicated. Pick a provider, enable encryption, schedule a daily or weekly backup job, and test a restore. The best backup is the one you actually verify.

If you want to build the local layer first, read our guides on self-hosted backup software and homelab security hardening.