Exhibit 99.1  LOGO March 12, 2019 Ms. Lee Ann Anderson PermRock Royalty Trust Simmons Bank, Trustee 2200 West 7th Street, Suite 210 Fort Worth, TX 76107  Re:

Evaluation Summary
PermRock Royalty Trust Net Profits Interest Proved Reserves
Various Counties, Texas As of December 31,
2018
 Dear Ms. Anderson: As requested, we are submitting our estimates of proved reserves and our forecasts of the resulting economics attributable to the above
captioned interests. We completed our evaluation on March 12, 2019. It is our understanding that the proved reserves estimated in this report constitute 100% of all proved reserves owned by PermRock Royalty Trust. This report has been prepared
for use in filings with the Securities and Exchange Commission. In our opinion the assumptions, data, methods, and procedures used in the preparation of this report are appropriate for such purpose. Composite reserve estimates and economic forecasts are summarized below:  ProvedDevelopedProducing


ProvedDevelopedNon-Producing


Proved Un-Developed


ProvedNet ReservesOil


 Mbbl



2,532.9



564.0



2,555.6



5,652.5Gas


 MMcf



1,381.8



844.1



1,764.3



3,990.2RevenueOil


 M$



146,739.8



33,158.9



151,167.0



331,065.6Gas


 M$



5,969.2



2,873.4



6,660.8



15,503.4Severance andAd Valorem Taxes


 M$



0.0



0.0



0.0



0.0Operating Expenses


 M$



0.0



0.0



0.0



0.0Investments


 M$



0.0



0.0



0.0



0.0Net Operating Income (BFIT)


 M$



152,708.9



36,032.3



157,827.8



346,569.1Discounted @ 10%


 M$



85,166.4



17,167.8



63,461.1



165,795.3 In accordance with the Securities and Exchange Commission guidelines, the operating income (BFIT) has been
discounted at an annual rate of 10% to determine its present worth. The discounted value shown above should not be construed to represent an estimate of the fair market value by Cawley, Gillespie & Associates, Inc. The annual average Henry Hub spot market gas price of $3.10 per MMBtu and the annual average WTI Cushing spot oil price of $65.56 per barrel
were used in this report. In accordance with the Securities and Exchange




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Evaluation Summary PermRock Royalty Trust Net Profits Interests As of
December 31, 2018 Page
 2
 of 7  Commission guidelines, these prices are determined as an unweighted arithmetic average of the first-day-of-the-month price for 12 months prior to the effective date of the evaluation. The oil and gas prices were held constant and were adjusted to wellhead prices by property based on
values supplied by Boaz Energy II, LLC (Boaz). Deductions were applied to the net gas volumes for fuel and shrinkage. The adjusted volume-weighted average product prices over the life of the properties are $58.62 per barrel of oil and
$3.97 per Mcf of gas. Operating expenses and capital costs for the underlying properties were supplied by Boaz and reviewed for
reasonableness. Severance tax rates were specified by property based on published state rates, with 50% oil severance tax abatements for 10 years on qualified waterflood projects. Ad valorem taxes were forecast as 2.48% to 3.5% of net revenue. As
per the Securities and Exchange Commission guidelines, neither expenses nor investments were escalated. The cost of plugging and the salvage value of equipment have not been considered. All proved reserve classifications conform to criteria of the Securities and Exchange Commission as set forth in Rules 4-10 of Regulation S-X and defined in pages 1 and 2 of the Appendix. The proved developed non-producing reserves include those
associated with behind-pipe zones, workovers and proved waterflood projects with current water injection and very minor remaining capital expenditures. The reserves and economics are predicated on the regulatory agency classifications, rules,
policies, laws, taxes and royalties in effect on the effective date except as noted herein. The possible effects of changes in legislation or other Federal or State restrictive actions have not been considered. The reserves were estimated using a
combination of the production performance, volumetric and analogy methods, in each case as we considered to be appropriate and necessary to establish the conclusions set forth herein. The methods employed in estimating reserves are described in page
3 of the Appendix. All reserve estimates represent our best judgment based on data available at the time of preparation and assumptions as to future economic and regulatory conditions. It should be realized that the reserves actually recovered, the
revenue derived therefrom and the actual cost incurred could be more or less than the estimated amounts. The reserve estimates were based
on interpretations of factual data furnished by Boaz and PermRock Royalty Trust. Ownership interests were supplied by and were accepted as furnished. To some extent, information from public records has been used to check and/or supplement these
data. The basic engineering and geological data were utilized subject to third party reservations and qualifications. Nothing has come to our attention, however, that would cause us to believe that we are not justified in relying on such data. An on-site inspection of these properties has not been made nor have the wells been tested by Cawley, Gillespie & Associates, Inc. Cawley, Gillespie & Associates, Inc. is independent with respect to PermRock Royalty Trust as provided in the Standards Pertaining to
the Estimating and Auditing of Oil and Gas Reserve Information promulgated by the Society of Petroleum Engineers (SPE Standards). Neither Cawley, Gillespie & Associates, Inc. nor any of its employees has any interest in the
subject properties. Neither the employment to make this study nor the compensation is contingent on the results of our work or the future production rates for the subject properties. Our work-papers and related data are available for inspection and review by authorized parties.  Respectfully submitted,LOGOCAWLEY, GILLESPIE & ASSOCIATES, INC.Texas Registered Engineering Firm F-693




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APPENDIX Reserve Definitions and Classifications The Securities and Exchange Commission, in SX Reg. 210.4-10 dated November 18, 1981, as amended
on September 19, 1989 and January 1, 2010, requires adherence to the following definitions of oil and gas reserves: (22)
Proved oil and gas reserves. Proved oil and gas reserves are those quantities of oil and gas, which, by analysis of geoscience and engineering data, can be estimated with reasonable certainty to be economically produciblefrom a
given date forward, from known reservoirs, and under existing economic conditions, operating methods, and government regulations prior to the time at which contracts providing the right to operate expire, unless evidence indicates that renewal
is reasonably certain, regardless of whether deterministic or probabilistic methods are used for the estimation. The project to extract the hydrocarbons must have commenced or the operator must be reasonably certain that it will commence the project
within a reasonable time. (i) The area of a reservoir considered as proved includes: (A) The area identified by drilling and
limited by fluid contacts, if any, and (B) Adjacent undrilled portions of the reservoir that can, with reasonable certainty, be judged to be continuous with it and to contain economically producible oil or gas on the basis of available
geoscience and engineering data. (ii) In the absence of data on fluid contacts, proved quantities in a reservoir are limited by the
lowest known hydrocarbons (LKH) as seen in a well penetration unless geoscience, engineering, or performance data and reliable technology establishes a lower contact with reasonable certainty. (iii) Where direct observation from well penetrations has defined a highest known oil (HKO) elevation and the potential exists for an
associated gas cap, proved oil reserves may be assigned in the structurally higher portions of the reservoir only if geoscience, engineering, or performance data and reliable technology establish the higher contact with reasonable certainty. (iv) Reserves which can be produced economically through application of improved recovery techniques (including, but not limited to,
fluid injection) are included in the proved classification when: (A) Successful testing by a pilot project in an area of the reservoir with properties no more favorable than in the reservoir as a whole, the operation of an installed program in
the reservoir or an analogous reservoir, or other evidence using reliable technology establishes the reasonable certainty of the engineering analysis on which the project or program was based; and (B) The project has been approved for
development by all necessary parties and entities, including governmental entities. (v) Existing economic conditions include prices
and costs at which economic producibility from a reservoir is to be determined. The price shall be the average price during the 12-month period prior to the ending date of the period covered by the report,
determined as an unweighted arithmetic average of the first-day-of-the-month price for
each month within such period, unless prices are defined by contractual arrangements, excluding escalations based upon future conditions. (6) Developed oil and gas reserves. Developed oil and gas reserves are reserves of any category that can be expected to be
recovered: (i) Through existing wells with existing equipment and operating methods or in which the cost of the required equipment
is relatively minor compared to the cost of a new well; and (ii) Through installed extraction equipment and infrastructure
operational at the time of the reserves estimate if the extraction is by means not involving a well. (31) Undeveloped oil and
gas reserves. Undeveloped oil and gas reserves are reserves of any category that are expected to be recovered from new wells on undrilled acreage, or from existing wells where a relatively major expenditure is required for recompletion.




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(i) Reserves on undrilled acreage shall be limited to those directly offsetting
development spacing areas that are reasonably certain of production when drilled, unless evidence using reliable technology exists that establishes reasonable certainty of economic producibility at greater distances. (ii) Undrilled locations can be classified as having undeveloped reserves only if a development plan has been adopted indicating that
they are scheduled to be drilled within five years, unless the specific circumstances, justify a longer time. (iii) Under no
circumstances shall estimates for undeveloped reserves be attributable to any acreage for which an application of fluid injection or other improved recovery technique is contemplated, unless such techniques have been proved effective by actual
projects in the same reservoir or an analogous reservoir, as defined in paragraph (a)(2) of this section, or by other evidence using reliable technology establishing reasonable certainty. (18) Probable reserves. Probable reserves are those additional reserves that are less certain to be recovered than proved
reserves but which, together with proved reserves, are as likely as not to be recovered. (i) When deterministic methods are used,
it is as likely as not that actual remaining quantities recovered will exceed the sum of estimated proved plus probable reserves. When probabilistic methods are used, there should be at least a 50% probability that the actual quantities recovered
will equal or exceed the proved plus probable reserves estimates. (ii) Probable reserves may be assigned to areas of a reservoir
adjacent to proved reserves where data control or interpretations of available data are less certain, even if the interpreted reservoir continuity of structure or productivity does not meet the reasonable certainty criterion. Probable reserves may
be assigned to areas that are structurally higher than the proved area if these areas are in communication with the proved reservoir. (iii) Probable reserves estimates also include potential incremental quantities associated with a greater percentage recovery of the
hydrocarbons in place than assumed for proved reserves. (iv) See also guidelines in paragraphs (17)(iv) and (17)(vi) of this
section (below). (17) Possible reserves. Possible reserves are those additional reserves that are less certain to be
recovered than probable reserves. (i) When deterministic methods are used, the total quantities ultimately recovered from a project
have a low probability of exceeding proved plus probable plus possible reserves. When probabilistic methods are used, there should be at least a 10% probability that the total quantities ultimately recovered will equal or exceed the proved plus
probable plus possible reserves estimates. (ii) Possible reserves may be assigned to areas of a reservoir adjacent to probable
reserves where data control and interpretations of available data are progressively less certain. Frequently, this will be in areas where geoscience and engineering data are unable to define clearly the area and vertical limits of commercial
production from the reservoir by a defined project. (iii) Possible reserves also include incremental quantities associated with a
greater percentage recovery of the hydrocarbons in place than the recovery quantities assumed for probable reserves. (iv) The
proved plus probable and proved plus probable plus possible reserves estimates must be based on reasonable alternative technical and commercial interpretations within the reservoir or subject project that are clearly documented, including
comparisons to results in successful similar projects. (v) Possible reserves may be assigned where geoscience and engineering data
identify directly adjacent portions of a reservoir within the same accumulation that may be separated from proved areas by faults with




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displacement less than formation thickness or other geological discontinuities and that have not been penetrated by a wellbore, and the registrant believes that such adjacent portions are in
communication with the known (proved) reservoir. Possible reserves may be assigned to areas that are structurally higher or lower than the proved area if these areas are in communication with the proved reservoir. (vi) Pursuant to paragraph (22)(iii) of this section (above), where direct observation has defined a highest known oil (HKO) elevation
and the potential exists for an associated gas cap, proved oil reserves should be assigned in the structurally higher portions of the reservoir above the HKO only if the higher contact can be established with reasonable certainty through reliable
technology. Portions of the reservoir that do not meet this reasonable certainty criterion may be assigned as probable and possible oil or gas based on reservoir fluid properties and pressure gradient interpretations. Instruction 4 of Item 2(b) of Securities and Exchange Commission Regulation S-K was revised
January 1, 2010 to state that a registrant engaged in oil and gas producing activities shall provide the information required by Subpart 1200 of Regulation SK. This is relevant in that Instruction 2 to paragraph (a)(2) states:
The registrant is permitted, but not required, to disclose probable or possible reserves pursuant to paragraphs (a)(2)(iv) through (a)(2)(vii) of this Item. (26) Reserves. Reserves are estimated remaining quantities of oil and gas and related substances anticipated to be
economically producible, as of a given date, by application of development projects to known accumulations. In addition, there must exist, or there must be a reasonable expectation that there will exist, the legal right to produce or a revenue
interest in the production, installed means of delivering oil and gas or related substances to market, and all permits and financing required to implement the project. Note to paragraph (26): Reserves should not be assigned to adjacent reservoirs isolated by major, potentially sealing, faults
until those reservoirs are penetrated and evaluated as economically producible. Reserves should not be assigned to areas that are clearly separated from a known accumulation by a non-productive reservoir
(i.e., absence of reservoir, structurally low reservoir, or negative test results). Such areas may contain prospective resources (i.e., potentially recoverable resources from undiscovered accumulations).




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APPENDIX Methods Employed in the Estimation of Reserves The four methods customarily employed in the estimation of reserves are (1)Production Performance,
(2)MaterialBalance, (3)Volumetric and (4)Analogy. Most estimates, although based primarily on one method, utilize other methods depending on the nature and extent of
the data available and the characteristics of the reservoirs. Basic information includes production, pressure, geological and laboratory
data. However, a large variation exists in the quality, quantity and types of information available on individual properties. Operators are generally required by regulatory authorities to file monthly production reports and may be required to
measure and report periodically such data as well pressures, gas-oil ratios, well tests, etc. As a general rule, an operator has complete discretion in obtaining and/or making available geological and
engineering data. The resulting lack of uniformity in data renders impossible the application of identical methods to all properties, and may result in significant differences in the accuracy and reliability of estimates. A brief discussion of each method, its basis, data requirements, applicability and generalization as to its relative degree of accuracy
follows: Production Performance. This method employs graphical analyses of production data on the premise that all factors
which have controlled the performance to date will continue to control and that historical trends can be extrapolated to predict future performance. The only information required is production history. Capacity production can usually be analyzed
from graphs of rates versus time or cumulative production. This procedure is referred to as decline curve analysis. Both capacity and restricted production can, in some cases, be analyzed from graphs of producing rate relationships of
the various production components. Reserve estimates obtained by this method are generally considered to have a relatively high degree of accuracy with the degree of accuracy increasing as production history accumulates. Material Balance. This method employs the analysis of the relationship of production and pressure performance on the premise
that the reservoir volume and its initial hydrocarbon content are fixed and that this initial hydrocarbon volume and recoveries therefrom can be estimated by analyzing changes in pressure with respect to production relationships. This method
requires reliable pressure and temperature data, production data, fluid analyses and knowledge of the nature of the reservoir. The material balance method is applicable to all reservoirs, but the time and expense required for its use is dependent on
the nature of the reservoir and its fluids. Reserves for depletion type reservoirs can be estimated from graphs of pressures corrected for compressibility versus cumulative production, requiring only data that are usually available. Estimates for
other reservoir types require extensive data and involve complex calculations most suited to computer models which make this method generally applicable only to reservoirs where there is economic justification for its use. Reserve estimates obtained
by this method are generally considered to have a degree of accuracy that is directly related to the complexity of the reservoir and the quality and quantity of data available. Volumetric. This method employs analyses of physical measurements of rock and fluid properties to calculate the volume of
hydrocarbons in-place. The data required are well information sufficient to determine reservoir subsurface datum, thickness, storage volume, fluid content and location. The volumetric method is most applicable
to reservoirs which are not susceptible to analysis by production performance or material balance methods. These are most commonly newly developed and/or no-pressure depleting reservoirs. The amount of
hydrocarbons in-place that can be recovered is not an integral part of the volumetric calculations but is an estimate inferred by other methods and a knowledge of the nature of the reservoir. Reserve estimates
obtained by this method are generally considered to have a low degree of accuracy; but the degree of accuracy can be relatively high where rock quality and subsurface control is good and the nature of the reservoir is uncomplicated. Analogy. This method, which employs experience and judgment to estimate reserves, is based on observations of similar situations
and includes consideration of theoretical performance. The analogy method is a




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common approach used for resource plays, where an abundance of wells with similar production profiles facilitates the reliable estimation of future reserves with a relatively high
degree of accuracy. The analogy method may also be applicable where the data are insufficient or so inconclusive that reliable reserve estimates cannot be made by other methods. Reserve estimates obtained in this manner are generally considered to
have a relatively low degree of accuracy. Much of the information used in the estimation of reserves is itself arrived at by the use of
estimates. These estimates are subject to continuing change as additional information becomes available. Reserve estimates which presently appear to be correct may be found to contain substantial errors as time passes and new information is obtained
about well and reservoir performance.