Kelsian Group (ASX:KLS) unit Transit Systems West signed a two-year contract extension with Transport for New South Wales for public bus services in the inner west region of Sydney, according to a Tuesday filing with the Australian bourse.

Services under the contract will start July 1, with the company securing about AU$500 million in additional revenue over the extension period, per the filing.

The contract includes the operation and maintenance of 528 buses from four depots, as well as a fleet replacement program to supply an additional 151 fully electric buses.