Every year career community CareerBliss analyses thousands of reviews to assess which American companies have the happiest employees. The survey highlights the companies that are succeeding in developing a happier working culture and a positive working environment for their staff. The Bliss Score covers factors such as company culture, leadership, overall work atmosphere, relationships with coworkers and CEO approval ratings. We count down this year's top 30 companies.

Microsoft achieved a Bliss Score of 3.876 and its CEO Satya Nadella received an 81% approval rating. The happiest employees here are network engineers and SQL developers. Employees were particularly happy with the people they work with, with this measurement scoring 4.3 out of 5. Support at work and the work setting also scored highly, with both getting 4.1 out of 5.

American Airlines received a Bliss Score of 3.897 and its chairman and CEO Doug Parker had a 77% approval rating. The happiest of its employees are customer service agents and aircraft maintenance technicians. Employees were most pleased with their work colleagues, scoring them at 4.4 out of 5. Management also did well, being rated at 4.3 out of 5.

Biopharmaceutical company Merck & Co. is headquartered in Kenilworth, New Jersey. Its Bliss Score was 3.93. Kenneth C. Frazier, the company chairman and CEO, scored an approval rating of 86%. The happiest Merck employees are managers and administrative assistants. Work colleagues got the highest score with 4.3 out of 5, closely followed by management with 4.2 out of 5.

Financial services business GE Capital is headquartered in Norwalk, Connecticut. It received a Bliss Score of 3.939. John Flannery, the company's chairman and CEO, received a 75% approval rating. Senior vice presidents and operations managers are the happiest workers here. Employees scored the people that they work with at 4.4 out of 5. The way of working and management both scored 4.3 out of 5.

Headquartered in New York City, American Express received a 3.942 Bliss Score. Stephen J. Squeri, the chairman and CEO, scored a high approval rating with 93%. QA analysts and sales representatives are the happiest workers here. Work colleagues scored 4.3 out of 5. The work setting and management both scored 4.2 out of 5.

Headquartered in Chicago, insurance company the Blue Cross Blue Shield Association received a Bliss Score of 3.959. President and CEO Scott P. Serota won an 82% approval rating. Claims examiners and executive assistants are the happiest workers here. Work colleagues scored 4.3 out 5. The way of working, management and the work setting all scored 4 out of 5.

Headquartered in Waco, Texas, American Income Life Insurance Company has a Bliss Score of 3.993. President and CEO Roger Smith received a 73% approval rating. General agents and insurance sales agents are the happiest of its employees. Its staff are happiest with the people they work with giving them 4.3 out of 5. The way of working here was given 4 out of 5.

Headquartered in Boston, financial services company Fidelity Investments received a Bliss Score of 3.998. President and CEO Abigail Johnson had one of the highest approval ratings at 94%. Senior project managers and QA engineers are the happiest members of the workforce. Work colleagues scored 4.5 out of 5 and management scored 4.3 out of 5.

Pharmaceutical company Pfizer Inc. is headquartered in New York City. It received a Bliss Score of 4.006. Its chairman and CEO Ian C. Read received a 90% approval rating. The happiest workers here are professional healthcare representatives and administrative assistants. Work colleagues scored 4.4 out of 5. The support the company gives, the work setting and the way of working all scored 4.3 out of 5.

Part of JP Morgan, banking group Chase is headquartered in New York City. It received a Bliss Score of 4.026. It has several divisional CEOs and the CEO approval rating was 85%. The happiest employees are loan processors and loan officers. Work colleagues were rated the highest with 4.3 out of 5 and the way of working scored 4.1 out of 5.

Not-for-profit healthcare provider Kaiser Permanente is headquartered in Oakland, California. It received a Bliss Score of 4.043. Chairman and CEO Bernard J. Tyson received an 85% approval rating. The happiest workers here are compliance auditors and pharmacy systems analysts. Work colleagues scored 4.3 out of 5. The way of working and the work setting both scored 4.1 out of 5.

Technology company Citrix Systems Inc. is headquartered in Fort Lauderdale, Florida. It received a Bliss Score of 4.059. Its CEO and president David Henshall received an 89% approval rating. The happiest workers here are senior software development engineers in tests. Work colleagues scored 4.1 out of 5 and the work setting scored 4 out of 5.

Investment management company the Vanguard Group Inc. is headquartered in Valley Forge, Pennsylvania. It received a Bliss Score of 4.066. Its president and CEO Mortimer J. Buckley received a 91% approval rating. No particular members of the workforce were singled out as being the happiest, but work colleagues scored the highest with 4.2 out of 5 and management scored 4.1 out of 5.

Headquartered in New Jersey, technology and service company the iGATE Corporation is now part of Capgemini. It received a Bliss Score of 4.081. Its CEO received an 88% approval rating, but due to a restructure it's not known who held this role at the time of the survey. The happiest workers here are technical leads and senior software engineers. Work colleagues scored the highest with 4.5 out of 5. The way of working scored 4.4 out of 5.

Mobile technology company Qualcomm is headquartered in San Diego, California. It received a 4.093 Bliss Score. CEO Steve Mollenkopf won a high 96% approval rating. The happiest employees here are software test engineers and interns. Work colleagues scored 4.3 out of 5. The way of working, management, workplace support and the work setting all scored 4.2 out of 5.

Headquartered in Reston, Virginia, technology company Leidos Inc. received a Bliss Score of 4.095. Chairman and CEO Roger Krone received an 84% approval rating. The happiest employees here are software engineers. Work colleagues were ranked as 4.5 out of 5. Management got 4.4 out of 5.

Mortgage lender Quicken Loans Inc. is headquartered in Detroit, Michigan. It won a 4.111 Bliss Score and its CEO Jay Farner received a phenomenal 100% approval rating. The happiest employees here are mortgage bankers and senior mortgage bankers. Work colleagues scored 4.6 out of 5. Management and the company culture scored 4.3 out of 5.

Technology company Apple Inc. is headquartered in Cupertino, California. It received a Bliss Score of 4.185. Its CEO Tim Cook won a 92% approval rating. The happiest people working for Apple are campus representatives and contractors. Work colleagues scored 4.4 out of 5. Workplace support scored 4.2 out of 5.

Starbucks Corporation received a Bliss Score of 4.191. Its president and CEO Kevin Johnson scored an 88% approval rating. Supervisors and district managers are the happiest employees here. Work colleagues scored 4.3 out of 5. The way of working and the work setting scored 4 out of 5.

Headquartered in Bloomfield, Connecticut, healthcare provider Cigna got a Bliss Score of 4.22. Its CEO David Cordani received a 92% approval rating. Senior specialists and application developers are the happiest workers here. The people that employees work with scored 4.2 out of 5 and management scored 4 out of 5.

Lawn care company TruGreen is headquartered in Memphis, Tennessee. It received a Bliss Score of 4.235. President and CEO David Alexander received a 75% approval rating. Lawn technicians and auditors are the happiest employees here. Work colleagues scored 4.2 out of 5, as did management.

Headquartered in Pittsburgh, Pennsylvania, PNC Financial Services Group Inc. got a Bliss Score of 4.236. Its chairman, president and CEO William S. Demchak achieved an incredible 100% approval rating. Its happiest employees are senior loan officers and financial consultants. Work colleagues scored 4.1 out of 5 and the way of working scored 4 out of 5.

Headquartered in New York City, biopharmaceutical company Bristol-Myers Squibb got a Bliss Score of 4.238. Its chairman and CEO Giovanni Caforio had a 67% approval rating. Its happiest employees are sales representatives and research scientists. Work colleagues were rated 4.5 out of 5. The way of working and management were rated 4.3 out of 5.

Tech finance company Intuit Inc. is headquartered in Mountain View, California. Its Bliss Score was 4.264. Its CEO Brad Smith achieved an impressive 96% approval rating. Programmer analysts and senior software engineers are the happiest workers here. Work colleagues scored 4.4 out of 5. The work setting scored 4.3 out of 5.

Headquartered in San Ramon, California, energy company Chevron Corporation achieved a Bliss Score of 4.27. Its chairman and CEO Michael K. Wirth achieved an approval rating of 94%. Interns and customer service representatives are the happiest workers here. Work colleagues scored 4.4 out of 5. Management, workplace support and the way of working all scored 4.3 out of 5.

Biotech company Amgen Inc is headquartered in Thousand Oaks, California. Its Bliss Score was 4.289. Chairman and CEO Robert A. Bradway received an 83% approval rating. QA analysts and project engineers are the happiest employees here. Work colleagues scored 4.4 out of 5. The work setting and the way of working both scored 4.2 out of 5.

Computer software company Adobe Systems Incorporated is headquartered in San Jose, California. It achieved a Bliss Score of 4.321. Shantanu Narayen, the chairman, president and CEO, received a 92% approval rating. Quality engineers and QA engineers are the happiest employees here. Work colleagues scored 4.4 out of 5 and the work setting scored 4.3 out of 5.

Freight brokerage firm Total Quality Logistics, known as TQL, is headquartered in Cincinnati, Ohio. It received a Bliss Score of 4.381. Its CEO Ken Oaks achieved an impressive 97% approval rating. Sales leaders and logistics account executives are the happiest workers here. Management scored a high 4.8 out of 5 while colleagues scored 4.7 out of 5.

Headquartered in Beaverton, Oregon, sportswear producer Nike attained a Bliss Score of 4.478. Chairman, president and CEO Mark Parker received a very strong 95% approval rating. Sales associates are the happiest employees here. The company culture and work colleagues both scored 4.3 out of 5.

Real estate company Keller Williams Realty ranked as the happiest American company to work for. Headquartered in Austin, Texas, it attained a Bliss Score of 4.483. President and CEO John Davis achieved an incredible 100% approval score. Real estate associates and executive assistants are the happiest workers here. The way of working scored 4.6 out of 5 and work colleagues scored 4.5 out of 5.