Nearly 129 million Americans spend at least one-third of their waking life at work. For this reason, job satisfaction can be critical to overall happiness and quality of life — and some companies appear to prioritize employee satisfaction more than others.

Based on 49 million reviews posted to Glassdoor, an online platform for employees to rate their employer, the average company has a rating of 3.4 out of 5. Scores below 3 are relatively rare, but there are several companies — many of them customer facing — with plenty of room for improvement. There are 16 large companies with scores of 2.6 and lower.

24/7 Wall St. used Glassdoor data to identify the worst companies to work for. This is not a Glassdoor commissioned report. We only considered large, U.S.-based companies and excluded government agencies and nonprofits from our analysis.

In a written exchange with 24/7 Wall St., Glassdoor career trends expert Amelia Green-Vamos laid out some of the most common shortcomings of the companies on this list. “Companies with low satisfaction are typically those that struggle with culture and values, visibility and trustworthiness of senior leadership, and career opportunities which we see among very highly rated companies.” To be sure, these same factors are among the most common complaints in employee-submitted reviews for companies on this list. In Contrast, reviews for the best companies to work for frequently express confidence in senior leadership.

Compensation also appears to play a role. The average pay for common positions in many companies on this list is relatively low, and many employees complain about infrequent raises. Many of the positions available at these companies also rank among the 25 lowest paying jobs in America.

Widespread dissatisfaction among employees can also be bad for business. Unhappy employees can undermine the customer experience and ultimately the brand’s reputation. It is likely no coincidence that many of these companies also rank among America’s most hated companies.

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