Serco ticked higher as booming demand for its immigration services prompted the outsourcer to raise some of its forecasts for the rest of the year.
Demand from the UK government for more staff to process asylum seekers and other migrants will mean a £280 million boost to revenue, it said.
Serco has faced heavy criticism for the service it provides from some quarters with one report in May suggesting there was a culture of institutional abuse among its centres.
The group added that the growing amount of immigration work offset the decline in Covid testing with revenues for the half year rising to £2.47 billion from £2.18 billion and operating profits jumping by 52% to £188 million.
As a result, Serco now expects a better outcome for free cash flow and year-end net debt than previously.
Shares rose 2.8p to 158p marking a 15% rise since the end of June.