Are you signed up for the Advantage plan where they automatically charge you and send you the Desktop program each November?
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...
Otherwise for a regular online account it can not be deleted. Just abandon it.
