I was surprised to see my refund decrease substantially when put in the year end value of my IRAs. Is this correct?

[dmertz · Accepted solution]

Yes, this is usually correct.  It suggests that TurboTax was not able to calculate the correct taxable amount of your traditional IRA distributions until you entered the year end balance, calculating a taxable amount that was too low by assuming a zero year-end balance until the year-end balance was entered.