HSBC Bank USA is freezing its older, long-standing pension plan and moving all of its 11,000 employees onto a single retirement plan that has been in effect for about a decade as it seeks to simplify and align its benefits programs nationwide.

The U. S. subsidiary of London- based HSBC Holdings Plc recently told all employees that, as of early 2011, its older, “legacy” pension plan will no longer accrue new benefits.

Existing benefits that have been accumulated will not be affected and “employees retain everything they earned,” said spokesman Neil Brazil. They also will accrue benefits for retirement under the new plan.

Most of its employees are already on the newer retirement plan, which was introduced in 1997 to replace the older pension. The change affects those longtime employees who have been with the company for at least 13 years, who were “grand-fathered” into the pension plan when HSBC stopped offering it more than a decade ago.

Brazil would not comment further on specifics of the pensions. “We remain confident that we continue to offer a complete benefits program,” he said. “This comes at a time when many companies are discontinuing their benefit programs, and we do strive to be consistent with the market.”

Similarly, the bank has also streamlined its health insurance plans across the company into a single package of consistent medical plans “designed to fit a range of needs that are competitive in the marketplace,” Brazil said.

“We do keep an eye out on the marketplace and our peers, and we’re confident that we do offer a wide range of programs for employees,” he said.

However, some employees are upset that they may lose potential retirement benefits in future years because the new pension plan is not as generous. And they say the new health plans involve higher deductibles and copays, and less generous coverage.

The actions are a result of the way in which the current U. S. bank was formed. HSBC, formerly Buffalo-based Marine Midland Bank, has grown over the past two decades through acquisitions of other banks and businesses, each of which had its own benefits program.

The goal of the changes is to streamline the company’s benefits programs into a single package for everyone, using the options that have been available to all new employees for a number of years.