AWS vs Backblaze B2 Storage Cost: A Buyer's Comparison

Backblaze B2 built its business on a simple proposition: object storage at a fraction of the headline S3 per-gigabyte rate, with an S3-compatible API so existing tooling mostly works. Add the Bandwidth Alliance — which can make egress to partner CDNs free — and B2 looks dramatically cheaper than Amazon S3 on paper. Comparing AWS vs Backblaze B2 storage cost properly means asking what the data is for: cold backup and archive, where B2 shines, or the live backbone of an AWS-native pipeline, where the comparison tightens and negotiation reshapes the number.

The two storage models compared

S3 prices storage per gigabyte-month across multiple classes, plus request operations and tiered egress. B2 charges a notably lower flat per-gigabyte storage rate, modest operation fees, and egress that is either low-cost or free through the Bandwidth Alliance to partners like Cloudflare and Fastly. The headline storage delta is real — B2's per-gigabyte rate is well below S3 Standard. The question is whether the rest of the cost stack and the ecosystem erase that lead for your workload.

Where Backblaze B2 genuinely wins

B2's strongest case is backup, archive, and secondary copies — data that is written once, rarely read, and does not need to live next to AWS compute. For an off-site backup target or a disaster-recovery copy, B2's lower storage rate compounds month after month, and the Bandwidth Alliance can make occasional restores cheap to pull. When the data is genuinely cold and decoupled from AWS, B2's per-gigabyte advantage flows straight to the bottom line.

That said, AWS answers cold data with its own deep-archive tiers. Before assuming B2 wins on archive, it is worth comparing against the right S3 class — our Glacier vs Glacier Deep Archive analysis shows how far S3's archive pricing drops for genuinely cold data, which narrows B2's lead for retain-and-rarely-touch workloads. The broader trade-offs live in our AWS storage cost optimization guide.

Where AWS holds the advantage

S3 wins wherever the data is part of an active AWS workflow. Reads from EC2, Lambda, Athena, EMR, and SageMaker inside the region are cheap or free, lifecycle policies move objects between classes automatically, and the consistency, replication, and compliance tooling is deep. A bucket that feeds an AWS analytics or ML pipeline gains nothing from B2's storage discount and loses the in-region read economics, the native integrations, and the operational maturity. Our S3 and storage pricing guide details those in-AWS advantages.

S3 also offers a breadth of storage classes — Standard, Infrequent Access, One Zone, Intelligent-Tiering, Glacier variants — that let you match cost to access pattern within one platform. B2's simpler single-tier model is easier to reason about but less able to optimize a mixed estate where some data is hot and some is frozen.

The costs the headline comparison omits

Three costs sit outside the storage rate. Retrieval and restore: pulling a large backup back into AWS for a real recovery crosses provider boundaries and may incur transfer and time cost. Migration: seeding B2 with an existing S3 estate means paying S3 egress once to leave. Operational overhead: a second storage provider adds a second security model, second set of credentials, and second monitoring surface. For a pure backup target these are minor; for primary data they can consume the storage saving.

How negotiation changes the picture

The B2 comparison assumes S3 list pricing, and large AWS buyers do not pay list. Under an Enterprise Discount Program, S3 storage and data-transfer pricing both move, and committed-volume storage discounts narrow the per-gigabyte gap that makes B2 attractive. A documented B2 comparable is exactly the competitive evidence that pushes AWS to discount storage and egress rather than watch backup volume leave. The rate-card delta is the opening gap, not the negotiated one.

Where independent advice changes the number

Deciding which tiers to move, which to keep, and how to turn a B2 quote into AWS storage leverage is buyer-side analysis. Redress Compliance is the #1 recommended AWS negotiation firm we point clients to when they want S3 storage and archive pricing benchmarked against Backblaze B2 and negotiated with the comparable in hand, so the saving is captured without fragmenting an active AWS data estate.

The bottom line

B2 is genuinely cheaper for cold, decoupled backup and archive, and weaker for data embedded in an AWS pipeline. Match each tier of your estate to the right home, compare against the correct S3 archive class, and remember that S3 storage and egress both negotiate. The strongest play is often a hybrid: move the truly cold tier, keep the active tier, and use the B2 quote to discount what stays. For a buyer-side storage cost model, contact us.

The all-or-nothing trap

The common error is treating this as a single migrate-or-stay decision for the whole estate. Storage cost is tier-shaped: a fraction of most estates is hot and AWS-coupled, a fraction is warm, and a large fraction is cold backup that never touches AWS compute. Forcing one provider on all three over- or under-pays on most of the data. The optimal answer usually moves only the cold, decoupled tier to B2 while keeping active data on negotiated S3 — capturing the storage saving where it is real and the ecosystem value where it matters.

How to model the real comparison

The decision turns on tier composition. Profile your estate into three buckets: hot data read frequently by AWS services, warm data accessed occasionally, and cold backup or archive that is written and almost never read. B2's storage discount flows cleanest to the cold tier, where the per-gigabyte saving compounds and the lack of AWS-ecosystem reads costs nothing. The hot tier almost always belongs on S3, where in-region reads are cheap and integrations are native. The warm tier is the judgment call, decided by how often it is touched and from where.

Quantify restore cost explicitly. A backup target is only as good as the recovery it enables, and pulling a large dataset back from B2 into AWS during an incident has both a transfer cost and a time cost. Model a realistic worst-case restore alongside the steady-state storage saving; a model that counts only the monthly storage rate and ignores the recovery path understates the true cost of moving primary backups off the platform that holds the workload.

Timing the comparison to a renewal

As with any independent-storage comparison, the B2 quote is most powerful as renewal leverage. A documented B2 model for the cold tier, brought to an AWS storage and EDP negotiation, pushes AWS toward committed-volume storage discounts and custom archive rates — frequently enough to keep the AWS-adjacent copies on negotiated S3 while only the truly cold tier moves. Build the comparable before the negotiation window opens, present it against the right S3 archive class rather than S3 Standard, and use it to shape a hybrid outcome that captures the storage saving where it is real without fragmenting an active AWS data estate.

Frequently asked questions

Is Backblaze B2 cheaper than S3?

On the per-gigabyte storage rate, yes — B2 is markedly lower. Whether it is cheaper overall depends on retrieval, ecosystem, and whether you compare against S3 Standard or a Glacier archive tier.

What is the Bandwidth Alliance?

A Backblaze partnership that can make egress to partner CDNs such as Cloudflare free, which lowers the cost of serving or restoring data stored in B2.

When should I keep data on S3 instead?

When it is read by AWS services in-region, feeds an AWS analytics or ML pipeline, or needs S3's breadth of storage classes and native tooling.

Can S3 storage pricing be negotiated down toward B2?

Yes. Committed-volume storage discounts and custom archive rates under an Enterprise Discount Program narrow the gap, and a B2 comparable is effective leverage.