South Korea raised its tax revenue forecast to a record 478.6 trillion won ($353.5 billion) this year, as an artificial intelligence boom fuels chipmakers' profits and a stock market rally lifts trading-related collections.

The government expects to collect 63.2 trillion won more than projected in its supplementary budget, the Ministry of Finance and Economy said Wednesday, citing that the semiconductor boom and stock market rally had been difficult to anticipate during budget planning.

The revised estimate is 28 percent above last year's receipts and an increase of 104.7 trillion won.

Corporate tax accounts for roughly half of that annual gain, underscoring the fiscal impact of surging earnings at Samsung Electronics and SK hynix. Collections are forecast to jump 61.2 percent to 136.4 trillion won, about 35 trillion won above the supplementary budget estimate.

The two chipmakers' combined operating profit forecast for this year has risen to 638 trillion won, compared to 339 trillion won when the supplementary budget was prepared in February and 81 trillion won when the original budget was drawn up last year.

Their earnings growth is spilling over into other tax receipts. Larger bonuses in the semiconductor and financial industries are lifting payroll tax collections, while special dividends and increased housing transactions are boosting taxes on dividend income and capital gains.

Income tax revenue is projected to rise 16.9 percent to 152.4 trillion won. The estimate incorporates Samsung's plan, announced last month, to pay 30 trillion won in third-quarter dividends.

The stock market boom is adding to the windfall. Securities transaction tax receipts are expected to more than triple to 12.4 trillion won, helped by higher trading volumes and a rise in tax rates. The government raised rates this year to 0.05 percent for Kospi transactions and 0.2 percent for Kosdaq trades.

Meanwhile, the government is counting on another year of strong revenue growth. Its proposed 2027 budget forecasts tax receipts of 584.4 trillion won, 22.1 percent above this year's revised estimate.

By Choi Ji-won (jwc@heraldcorp.com)