The country collected 19 trillion won in taxes in February, compared with 10.3 trillion won the previous year, according to the Ministry of Economy and Finance.
The tally came as capital gains tax income rose amid increased housing transactions and the payment of deferred taxes.
In February, the government's total revenue, including tax income, amounted to 39.8 trillion won, up 13.3 trillion won from a year earlier.
The country's gross expenditures grew 2.9 trillion won on-year to 56 trillion won due to an increase in spending on job creation and an economic recovery.
As a result, the country posted a fiscal deficit of 16.1 trillion won in February, compared with a shortfall of 26.6 trillion won a year ago, the data showed.
The managed fiscal balance, another key gauge of fiscal soundness calculated on a stricter term, logged a shortfall of 20.4 trillion won in February, smaller than a deficit of 29.3 trillion won the previous year.
The country's central government debt amounted to 853.6 trillion won in February, up 34.4 trillion won from a year earlier.
South Korea is widely expected to post a fiscal deficit this year as it seeks to keep its expansionary fiscal policy to tackle the COVID-19 pandemic.
The country's debt is expected to reach 965.9 trillion won this year, according to the finance ministry. (Yonhap)