You can start an auto-launched flow when a Task is started or completed.

In the Checklist Item, populate the flow name in

  • Flow Name Completed
  • Flow Name Start 

Note that for the Start option to work, the Task status needs to be switched to In Progress, which might not be triggered if the Task is directly closed.

The auto-launched flow is populated with the following context:

taskIdthe task id
whatIdthe id of the Related To object record
whoIdthe id of the user/contact/account
ownerIdthe user Id of the Assigned To
taskthe task object

Create Flow

Create an Autolaunched Flow.  

Define Variables

Create a New Resource - Variable  - e.g. the whatId (Related To Id):

API Name: whatId  --   Data Type: Text  --  Available for Input

or the task itself:

API Name: task  --   Data Type: Record  --  Available for Input

Retrieve the Related Record 

For the Id filter, select the variable {!whatId}

(or use the task record variable: {!task.WhatId})


In the Flow you might want to check that the Id is as expected, e.g. that it is an Account Id (i.e. Id starting with 001)