During 2015, 1.03 million customers moved their bank account to another provider, compared with 1.15 million in 2014.
The drop in numbers comes in spite of a high profile publicity campaign last September.
However, the Current Account Switching Service (CASS) said more people switched in the last quarter of 2015.
CASS was launched in September 2013, to promote more competition between banks, and better deals for customers.
"These figures show customer apathy towards current account switching remains entrenched," said Richard Neudegg, head of regulation at price comparison site Uswitch.
"A quicker, more efficient switch alone is not enough to encourage customers to change banks or to improve competition."
However, CASS said switching rates improved by 11% in the last quarter of 2015, as a result of the media campaign.
And it said more people were aware of the service than previously.
In October, the Competition and Markets Authority (CMA) said that people could save at least Â£70 a year if they changed their current account provider.
The number of people switching current accounts has fallen by more than 10% in the past year, the industry has said.