Mr. Chris Wright reports

DEFIANCE REPORTS HIGH GRADE DRILL RESULTS AT SAN ACACIO

Defiance Silver Corp. has provided an update on the current drilling campaign at the Zacatecas project. The campaign was designed to confirm the extension of the known mineralized structures both laterally and vertically as well as to validate the current geological model that will be used for the coming mineral resource estimate. The company continues to consistently encounter high-grade silver mineralization in multiple mineralized zones with lateral and vertical continuity in the Veta Grande system. This release contains results from five holes: DDSA-25-73 through DDSA-25-77, representing 2,553 metres of the 10,000-metre diamond drill program that began Sept. 12, 2025. The company has completed 12 drill holes to date and additional drill holes will be reported as the company receives the analytical results.

Highlights of results:

• DDSA-25-76 returned 3.55 m of 355.32 grams per tonne silver (from 176.38 m to 179.93 m) within a 22.57-metre interval grading 102.91 g/t Ag from (179.93 m to 198.95 m). This hole also returned 3.07 m of 579.27 g/t Ag (from 209.15 m to 212.22 m), including 0.55 m of 2,120 g/t Ag (from 209.15 m) within a wider interval returning 10.65 m grading 210.70 g/t Ag from (209.15 m to 219.80 m).
• DDSA-25-77 returned 3.01 m of 262.88 g/t Ag (from 286.18 m to 289.19 m), including 1.75 m of 431.58 g/t Ag (from 286.18 m to 287.93 m) with 0.37 m of 1,965 g/t Ag (from 286.18 m to 286.55 m), all hosted within a larger interval of 6.77 m (from 286.18 m to 292.95 m) grading 128.69 g/t Ag.
• DDSA-25-75 returned 2.35 m of 298.58 g/t Ag (from 255.17 m to 257.52 m), including 0.36 m of 1,595 g/t Ag (from 255.17 m to 255.53 m) within a 5.20-metre interval grading 149.25 g/t Ag (from 252.32 m to 257.52 m).

Table 1 -- table of results

Note: True thickness is assumed to be 50 per cent to 80 per cent of downhole width.

Discussion of results

Defiance announced the start of the drill program on Sept. 12, 2025. The information presented in this release includes approximately 2,553 metres of drilling of a minimum 10,000-metre drill program designed to collect additional data in the San Acacio proposed mineral resource area. These holes were designed to improve the main Veta Grande structural model and to infill poorly drilled zones as well as to test both mineralized hanging wall and footwall splays to the Veta Grande system. High-grade results over wide widths were encountered in holes DDSA-25-75, DDSA-25-76 and DDSA-25-77.

Through surface mapping and drilling, the company has been able to identify at least three blocks on the main Veta Grande structure. These blocks are delineated by major north-northwest-striking faults, where displacement of the veins, mineralization styles and vein splays occur. The displacement of the vein in the area of the coming mineral resource estimate, can be approximately 15 m to 30 m.

The current blocks are being delineated by the San Jose and San Genaro fault systems and are named as follows: NW block, Central block and SE block. The NW block includes the significant past-producing Carolina and Almaden pits. The Central block includes the past-producing Esperanza pit and part of the Guadalupe pits, one of the largest past-producing open pits at San Acacio. The SE block is part of Guadalupe to Refugio-Tiro Intermedio area.

DDSA-25-73: This hole re-entered historical drill hole SAD-17-29, an older drill hole that ended before reaching the Veta Grande structure. By re-entering, the company was able to prove the continuity of the Veta Grande structure on the SE block. Although the Veta Grande structure was intercepted and some silver values were detected, the hole returned no results greater than 100 parts per million silver.

DDSA-25-74: This hole re-entered DDSA-21-48. The Veta Grande structure was intercepted and some silver values were detected; the hole returned no results greater than 100 ppm Ag.

DDSA-25-75: The first objective of this hole was to better define the width of Veta Navidad and farther downhole, drill through high-grade veinlets arrangements and then intersect the Veta Grande structure. The intercept of Veta Navidad in this drill hole, which was designed to cut through the vein perpendicularly, is only 0.8 m, which confirms that it is indeed a narrow subvertical structure. The hole was successful in identifying high-grade veinlet arrays between the Veta Navidad and Veta Grande structures.

DDSA-25-76: This is an infill drill hole that targeted the intersection of Veta Grande with hangingwall splays that create a mineralized shoot below the past-producing Esperanza pit area that is coherent with a wide mineralized vein at surface. The highest values correspond to one of the modelled mineralized splays in Veta Grande vein system.

DDSA-25-77: This hole re-entered historical drill hole SAD-17-30A, which previously encountered drilling problems and did not intercept Veta Grande when it was drilled in 2017. This drill hole targeted SE block hangingwall splays and the Veta Grande structure. Hole DDSA-25-77 was successful in intercepting the Veta Grande structure but with low grades. The wide intercepts with high grades correspond to widely mineralized veinlet zones both in both the hangingwall and footwall of the Veta Grande. The company believe that these wide, mineralized, array zones have the potential to add ounces to the coming resource estimate.

Discussion of quality assurance/quality control and analytical procedure

Samples were selected based on the lithology, alteration and mineralization characteristics; sample size ranges from 0.25 m to two m in width. All altered and mineralized intervals were sent for assay. One blank, one standard and one duplicate were included within every 20 samples. Standard materials are certified reference materials (CRMs) from OREAS and CDN that contain a range of silver, gold, copper, lead and zinc values. Blanks, standards and duplicates did not detect any issues with the analytical results.

Samples were analyzed by ALS Chemex Laboratories, an independent analytical facility. Sample preparation was performed at the prep facility in Zacatecas, Mexico, and analyses were performed at the analytical facility in Vancouver, Canada. All elements except gold and mercury were analyzed by a multielement geochemistry method utilizing a four-acid digestion followed by ICP-MS detection (ME-MS61m); mercury was analyzed after a separate aqua regia digest by ICP-MS. Overlimit assays for silver, lead and zinc were conducted using the OG62 method (multiacid digest with ICP-AES/AAS finish). Gold was measured by fire assay with an ICP-AES finish (50-gram sample, Au-ICP22).

About Defiance Silver Corp.

Defiance Silver is an exploration company advancing the district-scale Zacatecas project, located in the historic Zacatecas silver district, the 100-per-cent-owned Tepal gold/copper project in Michoacan state, Mexico, and the newly acquired Green Earth Metals property portfolio in Sonora state. Defiance is managed by a team of proven mine developers with a record of exploring, advancing and developing several operating mines and advanced resource projects. Defiance Silver's corporate mandate is to advance its projects through capital-efficient exploration focused on resource growth and new mineral discoveries.

Qualified person statement

George Cavey, PGeo, is a qualified person within the meaning of National Instrument 43-101 and has approved the technical information concerning the company's material mineral properties contained in this press release.

We seek Safe Harbor.