My wife started this year as sole proprietorship and didn't had any profit from self employement previously. But as we fill jointly she had tax liability. Do she need to fill now a 1040-ES quaterly?

[VolvoGirl]

How did she have a tax liability on a Joint return?  You mean you owed tax on your income?  

[jvietto]

Yes. Last year she didn't had any activity. But as we are filling jointly we did a tax return with both our names and we paid taxes on my incomes.
This year she just started to work as sole proprietoship so I am not sure if she needs to fill this 1040-ES quaterly:
The fact that it is the first year and that she cannot base previous tax return makes me beleive that she shouldn't fill it.
But the fact that we (and so she) did a tax return this year on my incomes makes me beleive that she had tax liability and as consequence should fill it.

[Anonymous]

if her business operated at a loss., then there was no self employment tax and her loss reduced your joint return income taxes.  so she decreased the liability on the joint return .