>I chose the pre-TCJA rules because I thought it would result in lower tax than using the trust tax rate. ( I have 58K of taxable income in 2019 filing married separate.) However, the result was contrary and the calculation using Turbo Tax was that the child pays about 4K more tax compared to using trust tax rate.
Yes, I have seen the same thing, and I am sure this is an error on the part of TurboTax. The same child who was dinged for less than $200 when included on her parents' tax return in 2018 gets hit for nearly $3000 using the new rules. (She had a job summer of 2019 and tax was withheld, so she had to file her own 1040.) When I reverted to the supposedly punitive Kiddie Tax rules, the tax due dropped to about $900 including some FICA tax. As in your case, the parents' income was a bit more than $50,000. Just for fun, I added the girl's income to the parents' and came out to about $200 tax owed. This is what SHOULD have happened under the new rules -- the child's income taxed at the parents' rate.
