"Just as consumer wireless customers dread getting those data overage notifications, business wireless customers prefer the predictable budgeting and unrestricted employee access that comes with unlimited data plans, even if those plans cost more," said Peter Cunningham, Technology, Media, and Telecommunications Practice Lead at J.D. Power. "This is such a critical observation because it leads to a much larger adoption rate for unlimited plans and significantly higher levels of carrier loyalty among business customers."

Following are some of the key findings of the study:

• Huge satisfaction gap grows between unlimited and data allowance plans: Overall satisfaction is much higher among customers whose company uses unlimited wireless data (822 on a 1,000-point scale), compared with those whose company does not (782). This 40-point gap is nearly double the 21-point gap observed in the consumer market when comparing those who have unlimited data with those who have data allowances.

• Unlimited plan adoption rate and loyalty significantly higher: The rate of adoption of unlimited data plans is 69% among business customers, compared with just 27% in the consumer marketplace. Among business customers who have unlimited data plans, 80% say they either "definitely will not" or "probably will not" switch to another carrier. That number falls to 73% among business users who have data allowances.

• Unlimited texting and international roaming also drive higher satisfaction: Other wireless services associated with higher levels of satisfaction include unlimited texting (+22 points) and international roaming (+35).

• Customer satisfaction correlates to size of business: Overall satisfaction with business wireless services is 813 in the large enterprise segment; 797 in the small/midsize business segment; and 761 in the very small business segment.

Study Rankings

T-Mobile ranks highest in all three business segments covered in the study, scoring 849 in the large enterprise segment; 813 in the small/midsize business segment; and 805 in the very small business segment. AT&T ranks second in the enterprise segment (820); Sprint ranks second in the small/midsize business segment (800); and Verizon Wireless ranks second in the very small business segment (770).

The 2017 U.S. Business Wireless Satisfaction Study is based on responses from 2,707 wireless customers. The study measures overall satisfaction among three key segments: very small business (1-19 employees); small/midsize (20-499 employees); and large enterprise (500 or more employees). Satisfaction is measured across six factors: performance and reliability; offerings and promotions; cost of service; sales representative and account executive; billing; and customer service.