HSBC Bank USA is laying off about 60 workers in downtown Buffalo following a reorganization last week, with some positions transferred to third-party vendors that employees can apply to for jobs.

The U.S. subsidiary of London-based HSBC Holdings Plc, which sold its entire upstate New York branch network in May, said the affected jobs are mostly in its mailroom, marketing and money center areas, and most were in the One HSBC Center tower that used to be its headquarters. The money center physically handles cash for the bank, including stocking ATMs that the bank no longer has in the region.

Employees received notice of the job cuts, with varying termination dates, but they are being encouraged to apply for about 100 HSBC openings in Buffalo in commercial banking, mortgage underwriting, information management and call-center operations, said spokeswoman Juanita Gutierrez. She would not elaborate on the reasons for the cuts, or identify the third-party vendors that are taking on some positions.

“We regularly review our staffing needs to ensure they are aligned with needs of the business,” she said.

HSBC employs about 3,000 in the Buffalo area, mostly in the downtown tower and the nearby HSBC Atrium, as well as in its mortgage servicing facility in Depew.

HSBC, formerly Buffalo-based Marine Midland Bank before it was acquired by HSBC 25 years ago, has been reducing its U.S. operations as part of a global restructuring designed to cut up to $3.5 billion in expenses, get out of less profitable businesses and regions, and cut the bank’s staff by 30,000 over three years.

Launched in 2011, the restructuring led to the sale of 195 branches in upstate New York and southwestern Connecticut, with $15 billion in deposits, as well as the related retail and small-business banking operations, to First Niagara Financial Group. First Niagara then sold 64 branches to KeyCorp, Community Bank System and Financial Institutions, and closed 35 overlapping branches, for a net gain of about 100 offices.

HSBC also sold its U.S. credit card business to Capital One Financial Corp., and is transferring its mortgage business to PHH Corp., including a big part of its Depew operation. It’s also expected to announce plans to move out of the HSBC tower when its lease expires in October 2013.