
The figures include property funds and companies in the non-compliance and non-performing sectors.
Of the 474 companies, 388 made a net profit and 86 recorded losses.
The robust earnings were achieved despite the fragile state of economy, which has been hit by political instability and spiralling inflation.
Excluding companies under non-compliance and in the non-performing sectors, 453 companies' accumulated net profit for the first half rose by 46 per cent to Bt313.82 billion.
Companies in the SET100 Index delivered a combined net profit of Bt252.57 billion, a 38-per-cent increase from the corresponding period last year. Those in the SET50 Index posted a net profit of Bt233.79 billion, up 42 per cent.
PTT, PTT Exploration and Production, Thai Oil, Siam Cement and Siam Commercial Bank reported the highest net earnings.
The resources sector, which comprises energy firms, utilities and mining companies, posted the highest sectoral net profit at Bt131.02 billion, up 25 per cent from the same period last year.
Financials had the highest growth in percentage terms, with net profit rising by 316 per cent to Bt52.83 billion.
Property and construction recorded a net profit of Bt36.38 billion, up 8 per cent from the corresponding period last year.
Industrials' combined net profit amounted to Bt31.47 billion, a year-on-year jump of 132 per cent.
The technology sector had a combined net profit of Bt25.86 billion, rising 92 per cent, while the agro and food industry sector enjoyed a 164-per-cent rise in earnings with a combined Bt10.67 billion.
The consumer products sector saw a surge of 36 per cent to Bt3.93 billion.
The services sector, however, bucked the trend. Its combined net profit for the first six months slumped 6 per cent year on year to Bt21.66 billion.