However, the outlook for the continued growth in household spending is not clear, given weakening consumer sentiment in the wake of the deadly ferry accident last month.
The income of households consisting of two members or more averaged 4.4 million won ($4,300) per month during the January-March period, up 5 percent from 4.2 million won a year earlier.
When adjusted for inflation, income grew 3.9 percent. The growth rate was faster than the 1.7 percent gain during the final quarter of last year, the data showed.
Household expenditures also increased. Household consumption spending came to 2.65 million won per month in the first quarter, up 4.4 percent from a year earlier. Adjusted for inflation, it rose 3.2 percent.
The agency was unsure if spending would continue to expand in the months to come, given that consumer sentiment weakened in the wake of the deadly ferry accident last month.