Direct answer: at the Azure Retail Prices API on 9 November 2026 (eastus, USD, excluding tax/discounts), Azure Elastic SAN bills on provisioned capacity in two units, Base and Capacity only: Base LRS $0.08/GiB-month ($81.92/TiB-month), Capacity LRS $0.06/GiB-month ($61.44/TiB-month); ZRS $0.12 / $0.09 ($122.88 / $92.16/TiB-month), a 50% premium over LRS. Each Base TiB carries 5,000 IOPS + 200 MBps; Capacity TiB adds no performance. Examples: 10 TiB all Base = $819.20/month (50,000 IOPS/2,000 MBps); 100 TiB (20 Base + 80 Capacity) = $6,553.60/month (100,000 IOPS/4,000 MBps); 100 TiB (50+50) = $7,168.00 (250,000 IOPS/10,000 MBps); 100 TiB all Base = $8,192.00 (500,000 IOPS/20,000 MBps). Snapshots are not billed separately but consume SAN capacity; the first snapshot takes no space, later ones are incremental, up to 200 per volume. Volumes range from 1 GiB to 64 TiB, each up to 80,000 IOPS/1,280 MBps; SAN performance is shared across volumes and accessed over iSCSI.
This guide is for enterprise architects, storage/SRE, finance and procurement teams evaluating SAN migration to Azure, database/VDI/media shared block storage, or Elastic SAN versus ANF/Managed Disks/Azure Files. It explains Base/Capacity, LRS/ZRS, 1/10/50/100 TiB TCO, performance and volume caps, snapshots/autoscale, selection and a 90-day checklist. Prices come from the Azure Elastic SAN pricing page, the Azure Retail Prices API and Microsoft Learn (eastus, 9 November 2026). Official price facts, editorial calculations and exclusions are kept separate. This is not procurement advice.
(1) Base buys performance, Capacity buys capacity: a Base TiB carries 5,000 IOPS/200 MBps, Capacity adds only storage; size the mix by IOPS/throughput, not all Base. (2) ZRS costs 50% more than LRS; choose by zone/SLA needs. (3) Snapshots are not billed separately but consume SAN capacity; autoscale only adds additional capacity in 1 TiB steps and does not add IOPS/throughput.
Base vs Capacity: two provisioning units
Elastic SAN separates capacity from performance: a Base unit provides 5,000 IOPS + 200 MBps per TiB at a higher price; a Capacity only unit adds a TiB of storage with no IOPS/throughput at a lower price. Both bill hourly at a monthly rate, and ZRS costs 50% more than LRS. This suits "large capacity, low performance" or "small capacity, high IOPS" better than buying Premium SSD v2/Ultra per volume.
| Unit | Capacity | IOPS | Throughput | LRS/GiB-month | LRS/TiB-month | ZRS/GiB-month | ZRS/TiB-month |
|---|---|---|---|---|---|---|---|
| Base | 1 TiB | 5,000 | 200 MBps | 0.08 | 81.92 | 0.12 | 122.88 |
| Capacity | 1 TiB | — | — | 0.06 | 61.44 | 0.09 | 92.16 |
Sources: Azure Elastic SAN pricing page and Azure Retail Prices API (eastus, 9 November 2026); 1 TiB = 1,024 GiB, 730 hours/month. ZRS costs 50% more than LRS; hourly billing is converted from the monthly rate.
1 / 10 / 50 / 100 TiB TCO: size the mix by performance
Sizing Base/Capacity to provisioned IOPS/throughput: 1 TiB all Base $81.92/month (5,000 IOPS/200 MBps); 10 TiB all Base $819.20 (50,000/2,000); 10 TiB 5+5 = $716.80 (25,000/1,000); 50 TiB 20+30 = $3,481.60 (100,000/4,000); 100 TiB 20+80 = $6,553.60 (100,000/4,000); 100 TiB 50+50 = $7,168.00 (250,000/10,000); 100 TiB all Base = $8,192.00 (500,000/20,000). For the same 100 TiB, sizing to 100k IOPS saves $1,638.40/month (20%) versus all Base, and sizing to 250k IOPS saves $1,024.00/month (12.5%).
| Configuration | Capacity | Provisioned IOPS/MBps | LRS/month | ZRS/month |
|---|---|---|---|---|
| 1 TiB Base | 1 TiB | 5,000 / 200 | 81.92 | 122.88 |
| 10 TiB all Base | 10 TiB | 50,000 / 2,000 | 819.20 | 1,228.80 |
| 10 TiB 5+5 | 10 TiB | 25,000 / 1,000 | 716.80 | 1,075.20 |
| 50 TiB 20+30 | 50 TiB | 100,000 / 4,000 | 3,481.60 | 5,222.40 |
| 100 TiB 20+80 | 100 TiB | 100,000 / 4,000 | 6,553.60 | 9,830.40 |
| 100 TiB 50+50 | 100 TiB | 250,000 / 10,000 | 7,168.00 | 10,752.00 |
| 100 TiB all Base | 100 TiB | 500,000 / 20,000 | 8,192.00 | 12,288.00 |
Editorial calculation: Base $81.92/TiB-month, Capacity $61.44/TiB-month (LRS); ZRS $122.88/$92.16. Excludes VM, iSCSI clients, Private Endpoint, snapshot capacity, export/backup, tax and discounts.
Performance: Base scales, volumes cap, VMs cap again
Elastic SAN performance comes from Base TiB: 5,000 IOPS and 200 MBps per TiB, shared across all volumes. A single volume caps at 80,000 IOPS/1,280 MBps, with volume size from 1 GiB to 64 TiB; larger volumes can receive more performance, but the sum across volumes cannot exceed the SAN. Actual performance is also bounded by Azure VM IOPS/throughput limits; iSCSI can bypass a single VM's disk IOPS limit but not its network/CPU limit. Microsoft describes millions of IOPS, double-digit GB/s and single-digit millisecond latency.
| Item | Rule |
|---|---|
| Base performance | 5,000 IOPS + 200 MBps per TiB |
| Capacity performance | 0 IOPS / 0 MBps |
| Per-volume cap | 80,000 IOPS / 1,280 MBps |
| Volume size | 1 GiB–64 TiB |
| Performance allocation | SAN performance shared across all volumes |
| VM limit | VM IOPS/throughput limits still apply |
| Latency/scale | Single-digit ms; millions of IOPS, double-digit GB/s |
| Autoscale | Additional capacity only, 1 TiB steps, no performance |
Sources: Learn "Azure Elastic SAN introduction", "Plan for Elastic SAN", "Elastic SAN performance" (9 November 2026). Performance is vendor-described; calibrate with fio/VM testing.
LRS vs ZRS: 50% premium for zone redundancy
Elastic SAN supports LRS and ZRS: ZRS replicates across availability zones and costs 50% more. Both Base and Capacity carry the same premium: LRS 0.08/0.06, ZRS 0.12/0.09 per GiB-month. Choose ZRS for cross-zone SLA/DR; choose LRS for single-zone, cost-first workloads. Check ZRS regional availability, and do not confuse it with cross-region replication or backup.
| Redundancy | Base LRS/ZRS | Capacity LRS/ZRS | Price multiple | Use |
|---|---|---|---|---|
| LRS | 81.92 / — | 61.44 / — | 1× | Single zone, cost-first |
| ZRS | — / 122.88 | — / 92.16 | 1.5× | Zone redundancy/SLA |
Sources: Azure Elastic SAN pricing page and Retail API (eastus, 9 November 2026); unit TiB-month. ZRS regional availability follows the official page.
Snapshots and autoscale: no separate charge, but capacity is consumed
Elastic SAN volume snapshots are incremental: the first snapshot takes no space, and each later snapshot stores only changes since the previous one; snapshots are not billed separately but consume SAN capacity with the volumes. Each volume supports up to 200 snapshots at 7 per 5 minutes; deleting the source volume deletes its snapshots, so they are not durable backups—export to a managed disk snapshot for retention. Autoscale only expands additional capacity in 1 TiB steps and does not add Base/performance; 1 TiB of snapshot capacity costs about $61.44/month at Capacity LRS.
| Item | Rule | Cost/note |
|---|---|---|
| Snapshot billing | No separate charge | Consumes SAN capacity |
| First snapshot | No space | Later ones incremental |
| Snapshot limit | 200/volume, 7 per 5 min | Deleting source deletes them |
| Durable backup | Export to managed disk snapshot | Managed disk snapshot charges |
| Autoscale | Additional capacity only, 1 TiB steps | No IOPS/throughput added |
| 1 TiB snapshot capacity | Capacity LRS 61.44/month | ZRS 92.16 |
Sources: Learn "Snapshot Azure Elastic SAN volumes" and "Plan for Elastic SAN" (9 November 2026). Snapshots are not durable backups; export/backup and managed disk snapshot charges are extra.
Elastic SAN vs ANF vs Managed Disks vs Azure Files
Choose by protocol and performance model: Elastic SAN is iSCSI block storage with Base TiB performance pooled and shared across volumes, suiting SAN migration, database/VDI/media shared block devices; Azure NetApp Files is NFS/SMB file storage with service-level capacity pools and per-volume QoS; Managed Disks are per-VM block disks, simple but performance-bound per disk/VM; Azure Files is SMB/NFS file sharing for serverless/shared files. Elastic SAN's advantage is decoupled capacity/performance and multi-volume sharing, not replacing every block/file store.
| Scenario | Prefer | Why/check first |
|---|---|---|
| SAN migration/iSCSI shared block | Elastic SAN | Base/Capacity mix, iSCSI/MPIO |
| NFS/SMB enterprise files | Azure NetApp Files | Service level, capacity pool, per-volume QoS |
| Simple per-VM block disk | Managed Disks | Disk type/VM IOPS limit |
| SMB/NFS shared files | Azure Files | Protocol, performance tier |
| Very high per-volume IOPS | Premium SSD v2/Ultra or ANF | Per-volume/VM cap |
| Zone redundancy | Elastic SAN ZRS | +50% price, regional availability |
| Large capacity, low performance | Capacity units | Adds capacity, not performance |
| Snapshots/backup | Elastic SAN snapshots + export | Snapshots consume capacity, not durable |
Editorial selection framework, not a vendor recommendation; see each pricing page for ANF/Managed Disks/Azure Files. Sources: Learn docs and pricing page (9 November 2026).
Hidden costs and 90-day assessment checklist
Seven extra costs: VM IOPS/throughput limits (may need larger/more VMs), iSCSI/MPIO configuration and clients, Private Endpoint (hourly/traffic), snapshot capacity, export to managed disk snapshot, ZRS 50% premium and cross-region/egress data. 90-day assessment: weeks 1–2 inventory capacity, IOPS, throughput, latency, volume count and hosts; weeks 2–4 size 1/10/50/100 TiB with Base/Capacity; weeks 4–6 validate iSCSI/MPIO and VM caps; weeks 6–8 load-test per-volume/SAN performance and snapshots; weeks 8–10 compare ANF/Managed Disks/Azure Files; weeks 10–12 decide LRS/ZRS, autoscale and backup export.
FAQ
How is Azure Elastic SAN billed?
By provisioned capacity: Base LRS $0.08/GiB-month ($81.92/TiB), Capacity LRS $0.06 ($61.44/TiB); ZRS $0.12/$0.09 ($122.88/$92.16). Each Base TiB carries 5,000 IOPS/200 MBps; Capacity adds only capacity. Billing is hourly; ZRS costs 50% more than LRS.
What is the difference between Base and Capacity?
Base buys capacity + performance: 5,000 IOPS/200 MBps per TiB. Capacity buys only capacity with no IOPS/throughput, at a lower unit price. Size the mix by actual IOPS/throughput: large capacity/low performance uses more Capacity; high performance uses more Base.
How much is 100 TiB per month?
LRS: 20 Base+80 Capacity = $6,553.60 (100k IOPS/4,000 MBps); 50+50 = $7,168.00 (250k/10,000); all Base = $8,192.00 (500k/20,000). ZRS is about $9,830.40 / $10,752.00 / $12,288.00. Excludes VM/network/snapshots.
How much more is ZRS than LRS?
ZRS is 50% more: Base $0.12 vs $0.08, Capacity $0.09 vs $0.06 per GiB-month. Choose ZRS for zone redundancy/SLA; choose LRS for single-zone, cost-first workloads. Check ZRS regional availability.
How are snapshots charged?
Snapshots are not billed separately but consume SAN capacity; the first snapshot takes no space, later ones are incremental. Each volume supports up to 200 snapshots at 7 per 5 minutes; deleting the source volume deletes them. For long-term retention, export to a managed disk snapshot, which incurs managed disk snapshot charges.
How is performance calculated?
Each Base TiB provides 5,000 IOPS/200 MBps, shared across volumes; a single volume caps at 80,000 IOPS/1,280 MBps, with volume size 1 GiB–64 TiB. Azure VM IOPS/throughput limits also apply; iSCSI can bypass a single VM's disk limit but not its network/CPU.
How do Elastic SAN, ANF, Managed Disks and Azure Files compare?
Choose Elastic SAN for iSCSI block/multi-volume sharing; ANF for NFS/SMB enterprise files; Managed Disks for simple per-VM block; Azure Files for SMB/NFS shared files. For very high per-volume IOPS, consider Premium SSD v2/Ultra or ANF; for zone redundancy, Elastic SAN ZRS.
Does autoscale add performance?
No. Autoscale only expands additional capacity in 1 TiB steps and does not add Base, so IOPS/throughput stay the same. To add performance, manually add Base or re-plan the Base/Capacity mix.
Research method and limitations
This article separates "official price facts" from "editorial calculations": Base LRS $0.08/ZRS $0.12, Capacity LRS $0.06/ZRS $0.09, Base 5,000 IOPS/200 MBps, Capacity no performance, ZRS +50% and hourly billing come from the Azure Elastic SAN pricing page and Azure Retail Prices API (eastus, 9 November 2026); volumes 1 GiB–64 TiB, per-volume 80,000 IOPS/1,280 MBps, shared performance, snapshots not separately billed but consuming capacity, 200 snapshots/volume and autoscale 1 TiB additional-capacity-only come from Microsoft Learn (introduction, planning, snapshots, performance).
Eight limitations: (1) only eastus list prices, excluding tax/CSP/enterprise discounts; (2) 730-hour months; (3) the main TCO excludes VM, iSCSI clients, Private Endpoint, snapshot capacity, export/backup, cross-region/egress and tax; (4) performance is vendor-described and not fio/VM benchmarked; (5) the total SAN capacity limit is not listed (the doc example reaches 100 TiB; actual quota/region may vary); (6) ZRS regional availability is not checked one by one; (7) snapshots are not durable backups, and export/backup costs are not modelled; (8) prices/features change, so recheck official pages and bills before purchase.
Sources and basis
- Microsoft Azure, Azure Elastic SAN Pricing: azure.microsoft.com/en-us/pricing/details/elastic-san. Base/Capacity, LRS/ZRS, 5,000 IOPS/200 MBps, hourly billing. Accessed 9 November 2026.
- Azure Retail Prices API (productName contains Elastic SAN, eastus): prices.azure.com/api/retail/prices. $0.08/$0.06/$0.12/$0.09 per GiB-month. Accessed 9 November 2026.
- Microsoft Learn, Azure Elastic SAN introduction: learn.microsoft.com/en-us/azure/storage/elastic-san/elastic-san-introduction. iSCSI, shared performance, per-volume 80,000 IOPS/1,280 MBps, Private Endpoint/encryption. Accessed 9 November 2026.
- Microsoft Learn, Plan for Elastic SAN: learn.microsoft.com/en-us/azure/storage/elastic-san/elastic-san-planning. Base/Capacity mix, volumes 1 GiB–64 TiB, autoscale 1 TiB additional capacity only. Accessed 9 November 2026.
- Microsoft Learn, Snapshot Azure Elastic SAN volumes: learn.microsoft.com/en-us/azure/storage/elastic-san/elastic-san-snapshots. Incremental snapshots, no separate billing, capacity consumption, 200/volume, not durable backups. Accessed 9 November 2026.
Data cut-off 9 November 2026; prices/availability follow Microsoft official pages and bills; this is not procurement, commercial or legal advice.