The following is a summary of acts which authorized boundary changes for Obion County.
- Acts of 1824, Chapter 167, appointed Rice Williams, as a Surveyor to run and to mark the dividing boundary line between Obion County and Weakley County. Williams would be paid a reasonable compensation which would be shared equally by both counties, and he must be sworn according to law before beginning his task.
- Acts of 1847-48, Chapter 211, required the Surveyors of the Counties of Obion and Dyer to run and mark all the range and section lines in their respective counties which have not been heretofore run for which the Surveyors would be entitled to such fees as are provided by law. The Entry Takers of said Counties would pay the Surveyors their fees out of any funds in their hands which might belong to the State. If no State funds were available, then the Counties would pay the Surveyors.
- Acts of 1867-68, Chapter 13, Section 5, rearranged the boundary lines between Obion County and Weakley County beginning on the County line where it crosses the North Fork of the Obion River, running up the said River with its meanderings to Davis' Mills; thence north with the road leading from the Mill with the line of the Civil District until it reached the State line; thence west with the State line to the Obion County line; thence south to the point of the beginning.
- Acts of 1867-68, Chapter 20, Section 6, amends Acts of 1867-68, Chapter 13, by changing part of the description to read, so as to run up the North Fork of the Obion River with its meanderings to one mile above Davis' Mill; thence north to the Clinton Road; thence with the Clinton Road to the State line. Section 6 was expressly repealed by Acts of 1868-69, Chapter 5.
- Acts of 1867-68, Chapter 82, Section 4, changed the boundary line between Obion County and Weakley County starting from the north bank of the North Fork of the Obion River and running with it east of Davis' Mill, running in a northerly direction, so as to leave the land belonging to A. H. Walker in Obion County; thence in a northerly direction so as to strike the Clinton Road opposite G. W. Cannon's gate; thence with the Clinton Road to the State line.
- Acts of 1889, Chapter 76, changed the lines between Obion County and Weakley County so that the lands of J. W. Boyd and Company would be included wholly within Obion County, commencing at a point where the present County Line Road strikes J. W. Boyd's north boundary line and running thence north with Boyd's north line one-half mile to the State Line Road, which separates Tennessee and Kentucky; thence with the said State Line Road onequarter of a mile to where the present County line now strikes the State line.
- Acts of 1897, Chapter 176, recited that a Commission had been appointed to determine the line between Obion County and Lake County according to the Constitutional provision and the legislative Act creating Lake County, Acts of 1870, Chapter 30, and that the line had been determined by L. Donaldson of Lake County and S. F. Howard of Obion County. A lengthy metes and bounds description of the line is set out in this Act which constituted the work of the above named individuals. This particular Section was amended by Private Acts of 1925, Chapter 548. This Act is referred to in the case of State v. Hoffman, 210 Tenn. 686, 362 S.W.2d 231 (1962).
- Private Acts of 1931, Chapter 445, altered the lines between Obion County and Weakley County from the meanderings of the North Fork of the Obion River to the canal recently cut to straighten the said River's course, and the said Canal would henceforth be the north boundary of Weakley County and the south boundary of Obion County.