Archive contacts when account is archived

Archive contacts when account is archived

When a company goes out of business or gets acquired we mark it as inactive so that it will no longer appear in our lists.  When I do this I'd like all the contacts associated with it to also be marked inactive (but I do not want the association to go the other way, i.e. marking a contact inactive should not make the account inactive).  I need the contacts to be marked inactive so that they don't get synced with Zoho Campaigns for marketing purposes.  I've tried to setup a workflow rule, but I'm not seeing the option to update a contact field based on changing an account field.  Is there another way?