(a) When a member is purchasing TRS service credit for which the law requires that the actuarial cost or actuarial present value be deposited and for which the method in this section is referenced by another section of this title, TRS will calculate the cost using the cost factors obtained from the Actuarial Cost Tables adopted and method described in this section. For purposes of this section, TRS will use the age of the member and the service credit established by the member on September 1 of the school year in which the cost of the purchase is established.
(b) The factors for individuals whose membership was established before September 1, 2007 and who have five years of service credit on August 31, 2014, and maintain membership in TRS until the time of purchase, are shown in the tables adopted as part of this subsection. Within each set of tables, the number of years of service credit to be purchased will determine which specific table will be used. Each of the tables cross-references the member's age in rows with years of credited service (before purchase) in columns. The intersection of the participant's age and service is the cost per $1,000 of salary. The cost factor for a participant with more years of service credit than shown on the table is the same as the factor shown for the highest number of years of service credit on the table for the participant. TRS will calculate the cost to purchase service credit under this section by dividing the participant's salary by 1000 and multiplying the resulting quotient by the appropriate cost factor obtained from the table. The tables set forth the cost, per $1,000 of salary, to purchase from one year to fifteen years of service credit. The number of years of service credit available for purchase is determined by the laws and rules applicable to the type of service credit to be purchased. For the purpose of calculating the required amount for a member who is not grandfathered to use a three-year salary average under §51.12 of this title (relating to Applicability of Certain Laws in Effect Before September 1, 2005), the term "salary" is defined as follows:
  (1) For the upper region of the table (where the factors appear above the line), salary is the greater of the annual salary for the last year of credited service or the average of the member's highest years of compensation calculated on September 1 of the school year in which the cost of the service credit is established. The fewer of five years of compensation or all of the member's years of compensation shall be used for the average; or
  (2) For the lower region of the table (where the factors appear below the line), salary is the average of the member's highest five years of compensation calculated on September 1 of the school year in which the cost of the service credit is established. A member's highest five years of compensation shall be calculated as if the member were retiring at the time the service credit is purchased. The lower region of the table (where the factors appear below the line) reflects those age and service combinations where the purchase of service credit results in immediate eligibility of the member for unreduced retirement benefits.
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(c) For the purpose of calculation of actuarial cost for service credit for a member described in subsection (b) of this section who is grandfathered to use a three-year salary average, the term "salary" shall have the same meaning as in subsection (b) of this section except that a three-year salary average shall be used instead of a five-year salary average. Additionally, the cost shall be 103.5 percent of the cost as calculated under subsection (b) of this section.
(d) For individuals whose membership was established on or after September 1, 2007 and who have five years of service credit on August 31, 2014, and maintain membership in TRS until the time of purchase, the methodology described in subsection (b) of this section shall be used to determine cost of additional service credit, but TRS shall use the factors in the tables adopted as part of this subsection. If the member is not grandfathered to use a three-year salary average, the term "salary" shall have the same meaning as in subsection (b) of this section.
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(e) If an individual established membership on or after September 1, 2007 and has five years of service credit on August 31, 2014, and maintains membership in TRS until the time of purchase, but is grandfathered to use a three-year salary average, the term "salary" shall have the same meaning as in subsection (b) of this section except that a three-year salary average shall be used instead of a five-year salary average. The cost of establishing additional service credit for a grandfathered member described in this subsection, shall be 1.035 times the cost as calculated under subsection (d) of this section.
(f) An individual who first was a member of TRS before September 1, 2007, but who terminated membership through withdrawal of accumulated contributions and then again joined TRS on or after September 1, 2007, and has five years of service credit on August 31, 2014 and maintains membership in TRS until the time of purchase, is subject to the calculation of cost for additional service credit under subsections (d) and (e) of this section.
(g) For members who do not have five years of service credit on August 31, 2014 or whose current membership began after August 31, 2014, the methodology described in subsections (b) and (c) of this section shall be used to determine the cost of additional service credit, but TRS shall use the factors in the tables adopted as a part of this subsection.
Attached Graphic
(h) For the purpose of calculation of actuarial cost for service credit for a member described in subsection (g) of this section who is not grandfathered to use a three-year salary average, the term "salary" shall have the same meaning as in subsection (b) of this section.
(i) If the individual did not have five years of service credit on August 31, 2014 or whose current membership began after August 31, 2014, but is grandfathered to use a three-year salary average, the term "salary" shall have the same meaning as in subsection (b) of this section except that a three-year salary average shall be used instead of a five-year salary average. The cost of establishing additional service credit for a grandfathered member described in this subsection shall be 1.035 times the cost as calculated under subsection (g) of this section.
(j) The tables adopted in this section shall be used when the service credit cost is paid on or after September 1, 2023, or an installment agreement is entered into on or after September 1, 2023.

Source Note: The provisions of this §25.302 adopted to be effective March 8, 2007, 32 TexReg 1079; amended to be effective November 1, 2007, 32 TexReg 7693; amended to be effective January 5, 2012, 36 TexReg 9342; amended to be effective July 17, 2014, 39 TexReg 5432; amended to be effective December 23, 2014, 39 TexReg 10025; amended to be effective September 1, 2019, 44 TexReg 4185; amended to be effective September 1, 2023, 48 TexReg 4519