For the Advantage auto renew plan?  

You can sign into your Turbo Tax Advantage account and under Your Product, select to Remove Product.  Once you remove the recurring product order, the Turbo Tax Advantage subscription will be cancelled as well.

How to cancel Turbo Tax Advantage

https://ttlc.intuit.com/community/downgrading/help/how-do-i-cancel-my-turbotax-advantage-subscriptio...

Please cancel my Turbo Tax account. My user name is robcaro. My wife is handling my account now and will not use Turbo Tax. She has her own accountant.

Thank you,

Robert L Carothers

@robcaro 

No one here can cancel your Advantage account. We have no access to your account.  You have to do that for yourself.

https://ttlc.intuit.com/community/downgrading/help/how-do-i-cancel-my-turbotax-advantage-subscriptio...

Please, Please, Please CANCEL my account.  I can't afford to keep paying for it when I no longer need it!!!

@Robert Jacobs Good grief.  Did you read the reply that is posted DIRECTLY above your own post?  The one that says that no one else can access your account and cancel it for you?  Go up there and read what it says and then use the link provided so that you can cancel it yourself.

We will no longer need this account.   Please cancel.

@Robert Jacobs Again---no one can cancel your account for you.  If you need to cancel your Advantage account you have to do it for yourself.

https://ttlc.intuit.com/community/downgrading/help/how-do-i-cancel-my-turbotax-advantage-subscriptio...