Tax payments are due quarterly. There is a ten-day grace period. If the 10th falls on a weekend or a legal holiday you have until the next business day to make payment.
First Quarter
The first quarter is due February 1st and covers the months of January, February, and March.
Second Quarter
The second quarter is due May 1st and covers the months of April, May, and June.
Third Quarter
The third quarter is due August 1st and covers the months of July, August, and September.
Fourth Quarter
The fourth quarter is due November 1st and covers the months of October, November, and December.