What Is The Penalty For Cashing Out A 401K Early? 
Looks like David has covered the question pretty thoroughly so I 'll just give the short answer . When you withdraw from your 401K early - that is before reaching age 55 , you will be taxed on the entire amount . Then you will be penalized ten percent of the pre taxed amount . On top of that you may also have a percentage withheld for income tax for the year of withdrawal . 