From the Alliance for Retired Americans:

Today more than 70 million Americans work in private sector firms. Of that number, more than 10 million work in firms with fewer than 100 employees. Generally, the smaller the firm size, the less likely the firm will offer a defined benefit or defined contribution retirement plan to workers. Thus, Social Security benefits are especially important to the retirement income of workers in smaller firms.
According to the Congressional Research Service, only 29.3% of firms with fewer than 25 employees offered retirement plans, compared with 73.5% of firms with more than 100 employees. For firms with 25 to 99 employees, 53.7% of those firms offered retirement plans. Thus, the availability of retirement plans is more limited in smaller firms. In fact, the number of firms with fewer than 99 employees offering plans has declined during the past decade.
Read more from Spotlight: Social Security and Workers in Small Businesses »
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