> ## Documentation Index
> Fetch the complete documentation index at: https://docs.flowx.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Timer start event

> A Timer Start Event initiates a process instance based on a specified time or schedule.

![Timer Start Event node icon: a circle with a clock](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/3.5/timer_start_interrupting.png#center)

> [!NOTE]
>
> A swimlane can hold only one start node of any kind (Start Event, Message Start Event, or Timer Start Event). A process with several swimlanes can therefore have several Timer Start Events, one per swimlane, and each appears as its own row on the **Schedules** page.

## Configuration

The Timer Start Event supports two timer types:

| Timer Type | Description |
| - | - |
| Date | Specifies an exact date and time for triggering the event (ISO 8601 format) |
| Cycle | Specifies a repeating interval using ISO 8601 repeating intervals or cron expressions |

> [!NOTE]
>
> The Start Timer Event supports either ISO 8601 formats or Spring cron expressions for defining timer values. The value must be static: the **Process variable** mode (reading the value from the process data) is not available on this node, because no process instance exists yet when the timer fires.

> [!TIP]
>
> Starting a process via registered timers requires sending a process start message to Kafka, necessitating a service account and authentication. For detailed guidance, refer to:
>
> [**Service Accounts**](https://docs.flowx.ai/6.x/setup-guides/access-management/configuring-an-iam-solution.md#scheduler-service-account)

## Timer type details

### Date

Specifies an exact date and time for triggering the event. You can use ISO 8601 date format for accurate date-time representation.

Pick the date and time in the **Fire at** field (`yyyy-MM-dd HH:mm`, 24-hour clock). The time you pick is in your local time. The Designer converts it to UTC when it saves: 15:30 picked in a UTC+2 time zone is stored as `2025-03-12T13:30:00Z`.

![Timer Start Event configuration with the Date timer type, a UTC ISO definition, and the date and time pickers of the definition editor](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/470/start_timer_date.png)

### Cycle

Specifies a repeating interval for triggering the event. Select **ISO** or **Cron** under **Format** to choose the format. For the Cycle timer definition, you can use either:

#### ISO 8601 repeating intervals

For standardized time intervals (e.g., "R5/PT10M" for repeating 5 times with 10 minutes between each). Build the value with **Guided** fields, or switch to **Expression** and type it.

![Timer Start Event configuration with the Cycle timer type, an R5/PT10M definition, and the Repeat Every, number of repeats, Infinite, and Start Time controls of the definition editor](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/470/start_timer_cycle_iso_repeating.png)

> [!TIP]
>
> When configuring a Cycle timer (ISO 8601 repeating intervals) you can set:
>
> * **Repeat Every**: The interval between triggers, in plain words (e.g., "2 hours")
> * **# of repeats**: How many times the timer should trigger (e.g., "3")
> * **Infinite**: Option to make the timer repeat indefinitely
> * **Start Time**: When the timer should begin (`yyyy-MM-dd HH:mm`, your local time). It must be in the future.

#### Cron expressions

For more complex scheduling patterns (e.g., "0 0 12 \* \* MON-FRI" for 12:00 UTC every weekday). Type the Spring cron expression in the **Definition** field. Cron expressions are read in UTC.

Under **Active window**, set a **Start** and an **End** date and time. The timer fires only between them. Both are required, and both are in your local time.

![Timer Start Event configuration with the Cycle timer type, the Cron format selected, and a weekday noon cron expression as the definition](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/470/start_timer_cycle_cron.png)

#### Cron editor with required schedule window

The cron expression uses the six-field Spring format (second, minute, hour, day of month, month, day of week), for example `0 */5 * * * ?` for every five minutes. The **Start** and **End** of the active window are required on Timer Start Events. Once both are set, the preview under the definition shows the window in your local time zone, for example `Active window: 2026-11-02 09:00 – 2026-12-31 18:00 EET`, and the next three fire times. Next fires are counted from when you activate the schedule on the **Schedules** page.

![Cron definition editor of a Timer Start Event with the Cron expression field set to 0 0 2 \* \* MON-FRI and the Start Date, Start Time, End Date, and End Time fields filled in](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/06-timer-start-cron-editor-513.png)

![Timer Start Event configuration panel with the Cycle timer type, the Cron format selected, a weekday cron definition, and the Active window summary line under the definition](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/07-timer-start-cron-active-window-513.png)

The expression is validated before saving: exactly six fields, with support for lists, ranges, steps, `?`, `L`, `W`, `#`, month and weekday names, and the `@hourly`, `@daily`, `@midnight`, `@weekly`, `@monthly`, `@yearly`, and `@annually` macros. A seventh field is rejected with **Invalid cron expression.**

## Activate/deactivate start timer events

All timers can be activated/deactivated in **Runtime** → **Runtime Settings** → **Schedules**:

![Runtime Scheduled processes list with the activate and suspend controls for each timer start event](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/470/active_timer_events.png)

> [!WARNING]
>
> If a project contains multiple versions with Start Timer Event nodes, a scheduler will be generated only for the ones included in the version set in the active policy.
>
> ![Active policy dialog selecting the build whose timer start events are scheduled](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/470/Screenshot%202025-03-11%20at%2014.35.21.png)

## Usage examples

### Date timer example: Employee Onboarding Reminder

In this scenario, the Timer Start Event triggers an employee onboarding process at a specific date and time.

![Process canvas of the employee onboarding scenario: Timer Start Event, Employee Onboarding Notification task, and Complete Onboarding end](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/470/start_timer_event_scenario.png)

* Start Event (Timer Start Event) - New Hire Start Date
  * Timer Definition: 2023-09-01T09:00:00Z (ISO 8601 format) → This means the process will initiate automatically at the specified date and time.
  * This event serves as the trigger for the entire process.
  * Transition → Employee Onboarding Notification

![Timer Start Event configuration for the onboarding scenario with a Date definition of 2023-09-01T09:00:00Z](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/470/start_timer_date_scenario.png)

* Employee Onboarding Notification
  * Notify new employee about onboarding requirements by sending an email notification with a template called "Important Onboarding Information"
  * Actions: The HR team or automated system sends out necessary email information/documents, and instructions to the new employee.
  * After the notification is sent, the process transitions to the Complete Onboarding node.

![Send notification action configured with the Important Onboarding Information template](https://s3.eu-west-1.amazonaws.com/docx.flowx.ai/470/onboarding_notification.png)

* Complete Onboarding
  * Employee onboarding completed
  * At this point, the employee's onboarding process is considered complete.
  * Actions: The employee may have completed required tasks, paperwork, or orientation sessions.

### General rules

* Schedulers are generated only for builds that are part of the active policy.
* If you change the active policy, processes with Timer Start Event nodes might appear or disappear from the **Schedules** list if they aren't part of the active build.
* You can view scheduled timers in **Runtime** → **Runtime Settings** → **Schedules**.
* When a build in the active policy is updated with new Timer Start Event settings:
  * The scheduler is updated based on the new settings.
  * The scheduler state (active or suspended) remains the same as before.

***

## Related resources

> [card] [Timer expressions](https://docs.flowx.ai/6.x/docs/building-blocks/node/timer-events/timer-expressions.md)
>
> ISO 8601 and cron syntax for timer definitions

> [card] [Schedules](https://docs.flowx.ai/6.x/docs/projects/runtime/scheduled-processes.md)
>
> Activate, suspend, and review Timer Start Events at runtime

> [card] [Timer intermediate event](https://docs.flowx.ai/6.x/docs/building-blocks/node/timer-events/timer-intermediate-event.md)
>
> Pause a running process for a duration or until a date

> [card] [Starting a process](https://docs.flowx.ai/6.x/docs/flowx-designer/managing-a-project-flow/starting-a-process.md)
>
> All the ways a process instance can start


## Related topics

- [Initiating/starting processes](https://docs.flowx.ai/6.x/docs/flowx-designer/managing-a-project-flow/starting-a-process.md)
- [Timer events](https://docs.flowx.ai/6.x/docs/building-blocks/node/timer-events/timer-events.md)
- [Timer expressions](https://docs.flowx.ai/6.x/docs/building-blocks/node/timer-events/timer-expressions.md)
- [Schedules](https://docs.flowx.ai/6.x/docs/projects/runtime/scheduled-processes.md)
- [Process nodes (BPMN)](https://docs.flowx.ai/6.x/docs/building-blocks/node/node.md)


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