The Unite union said 850 staff would be axed, mainly in Southend, Essex.
It said the bank has announced almost 2,750 job losses since the start of the year.
Lloyds, HSBC and Barclays combined have announced cuts of around 5,500 jobs since the beginning of 2013, said Unite.
Lloyds' office in Southend is set to close, putting 690 jobs at risk, while the bank is also cutting another 160 roles across its commercial banking and bancassurance operations, said Unite.
National officer Dominic Hook said: "Lloyds is celebrating a return to profit and there are hints of dividend payouts to shareholders but the bank's workers are in constant fear that they will be next for the chop.
"This is no way to treat staff. It's time to urgently review this continuous tide of cuts and build the bank's strength. The constant job cuts across the banking industry is bad for bank staff, does nothing to support customers and it's bad for Britain's economy. Since January 5,500 job cuts have been announced by high street banks - that's over 1,000 a month.
Lloyds said the job losses are in its commercial banking, retail, group operations, group executive functions, finance, insurance, and wealth, asset finance and international divisions.
The bank said around 275 roles are being created, mainly in Belfast and Pitreavie, Scotland.