The Exchequer collected €5.9 billion in taxes last month, up 10% on January last year, according to figures published by the Department of Finance.
That contributed to a surplus of €1.666 billion, up €23m on last year.
Net voted expenditure was €4.575 billion, up 8.5% or €360m on January last year.
Income tax was up 16.7% or €315m to €2.2 billion.
VAT, however, was down slightly on January of last year by 1%.
January is the month when most VAT is collected.
Corporation tax yielded €116m, while excise duty was ahead of January 2019 by €48m or 10.4%.