Big banks trail smaller banks in overall customer satisfaction, but the gap is steadily shrinking, according a study released yesterday by JD Power and Associates.

“While big banks have traditionally had an advantage over smaller banks in terms of convenience of branch locations and technology, their disadvantage was often in the personal service customers desired,” said Jim Miller, senior director of banking at JD Power.

Big banks have made strides in customer service and explanation of fees, according to JD Power’s findings. Indeed, the financial services industry as a whole has made improvements in communicating with customers and meeting their needs, the study found.

Another factor behind big banks’s gains is mobile banking. While branch transactions continue to decline,  mobile transactions are on the rise, and big banks, with their deeper pockets, have traditionally had an advantage in the sophistication of their mobile offerings.  Mobile banking usage has risen to 17% of all transactions, up from 11% in 2012, and the average number of transactions has increased to 51 per customer per year, from 29 in 2012.

“Customers are quickly adopting mobile banking, making it a critical service channel for banks, not just a ‘nice to have’ option,” said Miller.

The study also ranked bank customer satisfaction by region, and JPMorgan Chase, despite being pilloried in the press on a daily basis, scored big wins in customer satisfaction. The bank rose to a fourth-place tie in customer satisfaction among 23 peer institutions, and scored first overall in the Midwest region.

While most other areas of the country were won by regional banks, TD Bank scored first in satisfaction in Florida.