The cost of setting up a 401(k) plan can be prohibitive to many startups, and research finds that areas dense with small businesses also tend to have the lowest access to retirement funds.

A new study from the Pew Charitable Trusts, A Look at Access to Employer-Based Retirement Plans in the Nation's Metropolitan Areas, analyzes the Current Population Survey (CPA) to determine which areas have workers with the best access to retirement programs (i.e., 401(k) and SEP IRA). It found that 58 percent of U.S. workers have access to such funds--though access varies greatly from city to city, more so than it does from state to state. Cities where workers had the most limited access were in large states, including Florida, Texas and California.

Those states also happen to have the highest number of fast growing, privately held companies in the U.S., according to the 2015 Inc. 5000 list. California came in at No.1 last year, with 681 businesses, followed by Texas, which had 423, and New York with 357. At. No. 4, Florida had 336.

As the Pew report notes, small businesses typically face more financial uncertainties -- especially as the venture capital climate has chilled in recent months, forcing even billion-dollar technology ventures to cut access to some employee benefits.

It's a sign of the times that Millennials are bitterly aware of. The generation is now the largest in the U.S., at roughly 80 million people, and globally, more than half of them expect to work past the age of 65, according to a recent study from HR consulting firm ManpowerGroup. As many as 12 percent said they expect to work until they die (and that figure climbs up to 37 percent in Japan).

Those with the best shot at a 401(k) plan live in Grand Rapid, Mich., according to the Pew study; 71 percent of those residents have access to retirement plans. The metropolitan area with the lowest access is McAllen, Texas, at just 23 percent. Overall, states in the South and the West of the nation tended to have lower access rates.

To remedy the problem, Pew says it's time for local and state governments to take action. Because industries with low access are typically concentrated in cities, government efforts have the potential to reach many workers. In New York City, for instance, Mayor Bill DeBlasio has proposed a retirement savings plan to reach private-sector workers in each of the five boroughs (1.4 million people total).

Similar proposals have passed, or are being considered, in California, Illinois and Oregon. On the national level, President Barack Obama's myRA plan, passed in 2015, is designed to give workers without access to corporate plans an alternative way to save, though  critics have pointed out that the myRA is largely funded by working poor, and has a relatively low savings cap of $15,000. The fund earns the same interest rate as the Government Securities Fund, which is low (about 3 percent) compared with the annual return of the S&P 500 Index.

Jane Bryant Quinn, the prominent financial journalist and co-founder of, hopes the next administration will do more than the previous to improve worker access to retirement funds. "It is a scandal that an automatic payroll deduction plan is not available to every single worker in this country," Bryant said in a previous interview with Inc.

"Your employment status should not make the difference between whether you have health insurance or not, and your employment status should not make the difference for whether you can make an automatic savings plan," she said.