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Any help would be appreciated.  I withdrew $22,723.14 from our 401K.  They withheld $2,272.31 for federal tax and $1,817.85 in state tax. I then paid back $15,000 during the year.

When I enter the 1099, Line 5 b calculates to $13,331 when I DON'T check the box to spread over 3 years and calculates tax based on that.  Shouldn't 5 b be $7,723 and the tax based on that?   I don't know where the $13,331 is coming from.

If I check the box for 3 years, then line 5b is zero and i get a substantial refund.

What am I missing?? 

Appreciate any insight.