Your New York tax liability might be higher than expected for a couple of key reasons.
1. If you earned income in multiple states but haven't properly divided up how much income was earned in each state, New York is calculating tax on all of your income. New York calculates tax liability based on all income and then prorates it based on how much New York source income you received. If you haven't let TurboTax know how much of your income was New York source, it will count all of your income as sourced to New York.
2. If you work for a New York based employer, New York has special rules that may allow them to tax all of your wages, even if you worked remotely from another state. This is called the "convenience of the employer rule" - basically if you're working remotely by choice rather than because your job necessitates it (for example, if your employer doesn't have a place for you work in New York), New York may still tax that income.
In the second case, if your income is taxable to New York and your state of residence, your resident state will generally allow a credit for the taxes that you pay to New York.
