Group revenue for the operator was up 18% year-on-year to £1.02bn ($1.24bn), with significant rises in Australia and the US.
However, retail revenue shrunk by 4% and the 8% rise in overall online revenue was chiefly due to Flutter’s acquisition of Adjarabet in Georgia.
Underlying EBITDA fell 10% to £196m, which Flutter attributes to an incremental £47m in taxes and duties; excluding these, the group says underlying EBITDA was up 15%.
It was Flutter’s profit levels which showed the largest decrease, down 24%, although the operator still made £81m for H1.
One of the reasons provided by the group was the "seasonality of the US business," where customer acquisition investment in both fantasy sports and sports betting was higher ahead of the NFL season – which starts in September.
Peter Jackson, Flutter Entertainment CEO, said: "We have had another productive six months at Flutter Entertainment plc.
"All divisions are performing strongly on an underlying basis and have responded well to the challenges faced. We are pleased with the progress we are making to build a more diversified and sustainable business."
Flutter’s share price rose from £6.20 to £6.35 in light of its H1 trading update. But it had steadily fallen from £6.58 during the first week of August.