Texas Local Government Code - LOC GOV'T § 112.010. County Fiscal Year

(a) The county fiscal year is the calendar year unless the commissioners court of the county adopts a different fiscal year as provided by Subsection (b) or (c).

(b) At a regular meeting, the commissioners court of a county may by order adopt as the county fiscal year a one-year period that begins on October 1 of each year.

(c) At a regular meeting, the commissioners court of a county with a population of 3.3 million or more may by order adopt as the county fiscal year a one-year period that begins on October 1 or March 1 of each year. In the order, the commissioners court may provide for the transition from one fiscal year to another by designating an interim fiscal year that may be longer or shorter than a 12-month period.

(d) The commissioners court of a county that has adopted a fiscal year under Subsection (b) or (c) may, by order adopted at a regular meeting, revert to a fiscal year that is the calendar year.

(e) If a law prescribes a certain date or month each year for an action relating to a county budget and the law is based on the assumption that the county fiscal year corresponds to the calendar year, in a county that has a fiscal year other than the calendar year the law shall be construed as prescribing a date or month that bears the same relationship to the beginning of the fiscal year that the specified date or month bears to January 1.