are both of you working? If so, you shouldn't claim the other one as dependant. Only children are dependant in this case. I guess only one should clain the children as dependant, the other one should claim 0 dependant. We don't have kids, so kids part is a gues. We both are working and put 0. But we have been paid back tax for a couple years. This year, it is even an unbelievable number. Should we put negative number? But someone said even you put negative number, HR may still consider it like 0 unless you ask them to withhold certain amount of money. Anyway, we were not asked to pay the penalty. So you shouldn't need to worry.