Income Tax and NI savings - which Account?

I have a seperate savings account which is for my Income Tax and NI, every month i transfer an amount from my Business account into the savings, this amount does not correspond to the actual Tax and NI i should pay but just whatever i can transfer. 

In my previous accounting software i was using an Equity account i called Tax/NI Savings to show the transactions, will this be the same in QB or should i be using another account?

I'm self employed and using QB Online.

Many Thanks

Chris