This July I moved from CA to CO. While in Colorado during that first month, I put in the paperwork to withdraw my entire retirement from the CalPERS (California Public Employees' Retirement System); I used some of the money to help with our moving costs and the rest went back into an IRA. I didn't receive my CalPERS refund check until around mid-September.

I'm trying to estimate the taxes that I'll owe this coming April. I know about all the early withdrawal fees, etc. I also know that I'll need to pay income tax on the amount I withdrew.

Here's my question: since I lived in CA for 6 months and will have lived in CO for 6 months once the year's done, which state's income tax rate should I use to figure out what I'll owe? Does it matter that I withdrew the money and received the money in CO?

Do I need to calculate that income tax based on the number of months I lived in each state (so half at the CA income tax rate and half at the CO income tax rate)? CO's state income tax rate is about half CA's income tax rate.

Thanks for any replies.