Control email's subject using API


I have an email that is being sent using single-send-api.
I pass different parameters using the API (to, custom properties...) however the subject is defined in the template.
I am looking for a way to override the subject, to pass a it as a parameter.
Is there a way to accomplish that?
The current work around I think about is having extra templates with the different subjects. But this solution is not so flexible and also hard to maintain.
Any ideas?


Hi @kerenc, there isn't a property you can send in the JSON body to update a single send api's subject line, but you can use contact and company personalization tokens in the subject if need be from the UI. Can you give me more context around what you're trying to accomplish by being able to edit the subject line each time you send out a transactional email?