# Service Level Agreement (SLA)

> For the complete documentation index, see [llms.txt](https://docs.temporal.io/llms.txt).
> Any documentation page is available as raw Markdown by appending `.md` to its URL.

> Standard Namespaces carry a 99.9% contractual guarantee against service errors and High Availability Namespaces carry 99.99%, measured per Namespace.

Temporal Cloud publishes two numbers for each deployment mode: the [service availability](https://en.wikipedia.org/wiki/Reliability,_availability_and_serviceability) it operates to, and the contractual [service level agreement](https://en.wikipedia.org/wiki/Service-level_agreement) (SLA) it guarantees against service errors.

| Deployment mode                                       | Service availability | Contractual SLA |
| ----------------------------------------------------- | -------------------- | --------------- |
| Standard single-region Namespace                      | 99.99%               | 99.9%           |
| Namespace using the [High Availability](/cloud/high-availability) feature | 99.99%               | 99.99%          |

The SLA that covers normal Worker requests, meaning commands and polling, also covers Nexus requests in both the caller and handler Namespaces.

## How the service-error rate is calculated

Temporal Cloud captures every request that arrives in a Namespace during a five-minute interval and records the gRPC service errors among them.
For each Namespace, the service-error rate is 1 - (count of errors / count of requests).
Rates are averaged per month and reset quarterly.

Errors counted against the SLA are service errors, such as the `UNAVAILABLE` [gRPC status code](https://grpc.github.io/grpc/core/md_doc_statuscodes.html).
The following errors are _not_ counted against the SLA:

- `ClientVersionNotSupported`
- `InvalidArgument`
- `NamespaceAlreadyExists`
- `NamespaceInvalidState`
- `NamespaceNotActive`
- `NamespaceNotFound`
- `NotFound`
- `PermissionDenied`
- `QueryFailed`
- `RetryReplication`
- `StickyWorkerUnavailable`
- `TaskAlreadyStarted`
- `Throttling (resources exhausted; triggers retry)`
- `WorkflowExecutionAlreadyStarted`
- `WorkflowNotReady`

## How Temporal measures against the SLA

Temporal alerts on a [service level objective](https://en.wikipedia.org/wiki/Service-level_objective) (SLO) that covers all errors, not only the errors that count against the SLA.
A missed SLO pages an on-call engineer, so many issues are resolved before they are noticeable.

Temporal Cloud runs a cell architecture.
Each cell holds the software and services needed to host a Namespace, and the components in a cell are distributed across at least three availability zones per region.

For current system status and recent incidents, see [Temporal Status](https://status.temporal.io).