Subscription to what? There is no subscription for the Online version. If you have the Desktop program Advantage plan for auto renewal 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...
