Direct answer: at the Azure Retail Prices API on 9 November 2026 (eastus, USD, excluding tax/discounts), Azure Event Grid has two tiers: Basic bills per operation at $0.60/million operations, first 100,000/month free; Standard (Namespace) adds MQTT operations $1.00/million (first 1M free), event operations $0.60/million (first 1M free) and Throughput Units $0.04/hour (about $29.20/month), up to 40 TU per namespace. Key detail: each operation is charged per 64KB data unit—events/messages over 64KB count as multiple operations—and each push delivery attempt (including 24-hour retries) counts as an operation. At one operation per event: 10M Basic about $5.94/month, Standard about $5.40; 100M about $59.94/$59.40; 1B about $599.94/$599.40. MQTT 10M about $9.00.
This guide is for Azure integration/event-driven architecture, IoT, SRE and FinOps teams. It explains Event Grid Basic/Standard, operations/MQTT/Throughput Units, the 64KB billing unit, retries/dead-letter/filtering, 10M/100M/1B TCO, and the boundary versus Event Hubs/Service Bus. Prices come from the Azure Event Grid pricing page and Azure Retail Prices API (eastus, 9 November 2026); features/retry/64KB rules come from Microsoft Learn's Event Grid overview/pricing page. Official price facts, editorial calculations and exclusions are kept separate. This is not procurement advice.
(1) Watch the billing unit: Basic bills operations; Standard bills MQTT/event operations + TU; operations are per 64KB unit, so large payloads multiply. (2) Retries cost money: push delivery retries for 24 hours and each attempt counts; more failures/subscribers amplify the bill. (3) Event Grid is routing/notification, not streaming storage: use Event Hubs for high-throughput durable streams and Service Bus for queues/commands.
Two tiers: Basic vs Standard (Namespace)
Basic provides discrete event publish/subscribe with custom topics, system topics, partner topics and domains, billed per operation. Standard uses an Event Grid Namespace with MQTT v3.1.1/v5.0 broker, pull/push delivery, custom domains and higher throughput (up to 40 TU per namespace), billed by TU + MQTT operations + event operations. Both support advanced filtering; push delivery retries for 24 hours with exponential backoff; each operation is charged per 64KB data unit.
| Item | Basic | Standard (Namespace) |
|---|---|---|
| Billing | Operations/million (first 100k free) | TU + MQTT operations + event operations |
| Protocols | HTTP events | MQTT v3.1.1/v5, HTTP pull/push |
| Resources | Custom/system/partner topics, domains | Namespace, topics, custom domains |
| Throughput | Per operation | Pre-purchased TU, up to 40/namespace |
| Retries | Push 24h exponential backoff | Push 24h; pull controlled by client |
Sources: Azure Event Grid pricing page and overview (9 November 2026). Editorial summary; features/limits follow official docs.
Unit prices: operations, MQTT, TU and free grants
Eastus list prices: Basic operations $0.60/million, first 100k/month free; Standard MQTT operations $1.00/million (first 1M/month free), event operations $0.60/million (first 1M/month free), Throughput Unit $0.04/hour (about $29.20/month). Each operation is per 64KB data unit; each push delivery attempt (including retries) counts as an operation.
| Item | Price (USD) | Free grant |
|---|---|---|
| Basic operations | $0.60/million | 100k/month |
| Standard event operations | $0.60/million | 1M/month |
| Standard MQTT operations | $1.00/million | 1M/month |
| Throughput Unit | $0.04/hour | None; about $29.20/month/TU |
| Billing unit | Per 64KB | Large payloads multiply |
Sources: Azure Retail Prices API (eastus, 9 November 2026) and Event Grid pricing page. Tax/discounts excluded; TU monthly uses 730 hours.
TCO: 10M / 100M / 1B operations
At one 64KB operation per event, no retries: 10M Basic (10M−100k)×$0.60/M=$5.94; Standard (10M−1M)×$0.60=$5.40. 100M: Basic $59.94, Standard $59.40. 1B: Basic $599.94, Standard $599.40. MQTT 10M: (10M−1M)×$1.00=$9.00; 100M $99.00; 1B $999.00. Standard adds TU (1 TU about $29.20/month).
| Operations/month | Basic | Standard events | Standard MQTT |
|---|---|---|---|
| 10M | 5.94 | 5.40 | 9.00 |
| 100M | 59.94 | 59.40 | 99.00 |
| 1B | 599.94 | 599.40 | 999.00 |
| +1 TU | — | +29.20 | +29.20 |
Editorial calculation: 1 operation/event, 64KB, no retries; free grants deducted; TU/retries/dead-letter/egress/tax/discounts excluded.
64KB and retries: bill amplifiers
Event Grid charges per 64KB data unit: a 256KB event = 4 operations; 1MB = 16. Push delivery counts every attempt: if 10% of events fail and retry 3 times, that adds 1M×3=3M operations, turning 10M events into 13M operations; Basic about (13M−100k)×$0.60=$7.74. More subscribers, retries and larger payloads push the bill away from “events × unit price.”
| Scenario | Operation multiplier | Note |
|---|---|---|
| ≤64KB | 1× | Standard event |
| 256KB | 4× | Per 64KB unit |
| 1MB | 16× | Large payload costs more |
| 10% failure×3 retries | +30% | 10M→13M operations |
| Multiple subscribers | Per delivery | Each subscription delivered |
Editorial calculation: official “per 64KB operation” and “each delivery attempt counts” rules; actual retries/subscriptions follow configuration.
Hidden costs: seven items beyond operations
Common add-ons: 64KB multiplier (large events/messages), retries/multiple subscribers (every delivery attempt), dead-letter/storage (dead-letter target), advanced filtering (filtering itself counts as operations), TU (Standard pre-purchased capacity), egress/network (cross-region/public delivery), namespace/custom domain/certificates and downstream consumers (Functions/Event Hubs/Service Bus extra).
| Cost item | Trigger | Control |
|---|---|---|
| 64KB multiplier | Large payload | Split/compress/reference |
| Retries/multiple subscribers | Failures/fan-out | Idempotency, fewer subscriptions, backoff |
| Dead-letter/storage | Failed delivery persisted | Cleanup/retention |
| Advanced filtering | Attribute filters | Simplify filters |
| TU | Standard capacity | Size TU by throughput |
| Egress/network | Cross-region/public | Same region/private endpoint |
| Downstream consumers | Functions/EH/SB | Model separately |
Sources: Event Grid pricing/overview docs (9 November 2026). Editorial summary; billing follows official pages and bills.
How to choose: Event Grid vs Event Hubs vs Service Bus
Event Grid fits event routing/notification/fan-out: system events, app events, partner events, IoT MQTT—low cost, per operation; Event Hubs fits high-throughput streaming/telemetry/logs, billed TU/PU/CU + ingress; Service Bus fits queues/commands/transactions/dead-letter, billed per operation/message. They often combine: devices → Event Grid/Event Hubs → Functions/Service Bus → business systems.
| Scenario | Prefer | Check first |
|---|---|---|
| Event notification/fan-out/system events | Event Grid | Operations/64KB/retries |
| High-throughput streaming/telemetry | Event Hubs | TU/PU/CU, retention |
| Queues/commands/transactions | Service Bus | Operations/messages, dead-letter |
| IoT MQTT | Event Grid Standard | TU, MQTT operations |
| Cross-system integration | Event Grid + Functions | Delivery/retries/downstream |
| Large payload | Split/object-store reference | 64KB multiplier |
Editorial selection framework, not a vendor recommendation; features/compliance/regional availability follow official docs and business requirements.
90-day checklist
Use the first 90 days to close “event volume/payload → subscriptions/retries → billing unit → pilot → monitor → review.” Weeks 1-2: pull events, average/peak payload, subscriptions, failures/retries; weeks 2-4: calculate 64KB and retry multipliers; weeks 4-6: choose Basic/Standard, TU/namespace; weeks 6-8: pilot dead-letter/filtering; weeks 8-10: cut over/monitor; weeks 10-12: cost review, compression/fewer subscriptions. Do not estimate by “events × unit price” alone.
FAQ
How is Event Grid billed?
Basic per operation $0.60/million (first 100k free); Standard MQTT $1.00/million (first 1M free) + events $0.60/million (first 1M free) + TU $0.04/hour. Each operation is per 64KB data unit.
How much is 10M events?
At 1 operation/64KB: Basic about $5.94/month, Standard about $5.40; MQTT about $9.00; Standard adds TU (1 TU about $29.20).
Why is the bill higher than the event count?
Each operation is per 64KB, so large payloads cost 4×/16×; every push attempt (including 24h retries) counts; multiple subscribers each get a delivery.
Are retries billed?
Each push delivery attempt counts as an operation, including the 24-hour retry; pull delivery is controlled by the client and billed per operation.
Basic or Standard?
Basic for discrete/system events/domains only; Standard for MQTT, pull/push, Namespace, custom domains/higher throughput (TU + operations).
What is a TU?
A Throughput Unit is pre-purchased capacity for a Standard namespace at $0.04/hour (about $29.20/month), up to 40 TU per namespace. Size by throughput.
Event Grid or Event Hubs?
Event Grid for event routing/notification/fan-out; Event Hubs for high-throughput streaming/telemetry/logs. Use Event Hubs for durable streams/replay, Event Grid for event distribution.
Event Grid or Service Bus?
Service Bus for queues/commands/transactions/dead-letter; Event Grid for pub/sub event notification. They can combine (Event Grid triggers, Service Bus queues).
Research method and limitations
This article separates “official price facts” from “editorial calculations.” Basic operations, Standard MQTT/event operations, TU, free grants and the 64KB billing unit come from the Azure Event Grid pricing page and Azure Retail Prices API (eastus, 9 November 2026); Basic/Standard features, MQTT, 24h retries, pull/push and 40 TU come from Microsoft Learn's Event Grid overview/pricing page. TCO, 64KB/retry multipliers, hidden costs and the 90-day checklist are editorial.
Eight limitations: (1) only eastus list prices, excluding tax/discounts/enterprise agreements; (2) 1 operation/event, 64KB, no retries; (3) TU/dead-letter/egress/downstream/tax combinations are excluded; (4) no real high-throughput/retry/fan-out benchmark; (5) MQTT operations/connections/session details are not fully covered; (6) partner/domain/custom-domain billing is not fully covered; (7) Basic/Standard regional differences are not covered; (8) prices/features change, so recheck official pages and bills before purchase.
Sources and basis
- Microsoft Azure, Event Grid Pricing: azure.microsoft.com/en-us/pricing/details/event-grid. Basic/Standard, operations/MQTT/TU, free grants, 64KB. Accessed 9 November 2026.
- Azure Retail Prices API (productName contains Event Grid, eastus): prices.azure.com/api/retail/prices. 0.60/1.00/0.04 and free meters. Accessed 9 November 2026.
- Microsoft Learn, Azure Event Grid overview: learn.microsoft.com/azure/event-grid/overview. Basic/Standard, MQTT, 24h retries, pull/push, filtering. Accessed 9 November 2026.
Data cut-off 9 November 2026; prices/availability follow the Azure official page and bill; this is not procurement, commercial or legal advice.