July 21 (Reuters) - Walmart Inc said on Tuesday it would spend another $428 million on bonuses this year, to compensate its U.S. employees for catering to a surge in demand for essential goods during the COVID-19 pandemic.

The United States' largest employer said the new spending brings the total expenditure on employee bonuses to $1.1 billion this year.

Walmart, like other essential retailers, has seen a spike in demand for groceries and has had to add hundreds of thousands of new hourly workers to keep up. However, those costs as well as the expenditure to keep stores operating safely have pressured its profit margins.

The company said full-time hourly employees will get a $300 bonus, while part-time and temporary employees will get $150, adding that drivers, managers and assistant managers will also receive a bonus.

The world's largest retailer also said it would close its own and Sam's Club outlets on Thanksgiving day this year.

(Reporting by Uday Sampath in Bengaluru; Editing by Amy Caren Daniel)