Is A 401K Considered A Retirement Plan? 
Yes . It is an employer sponsored , defined contribution plan under section 401 -LRB- k -RRB- of the tax code . They were introduced around 1980 as an alternative to defined benefit pension plans . They have become popular but have had their critics especially during the financial crisis when some referred to them as 201 -LRB- k -RRB- over market losses . 