Background/Objectives: The aim of this paper was to evaluate the two-year outcomes of phacoemulsification combined with gonioscopy-assisted transluminal trabeculotomy (PHACO-GATT) versus standalone GATT in terms of efficacy, safety, and surgical success. Methods: This retrospective, comparative study included 64 eyes of 64 patients with moderate-to-severe open-angle glaucoma: 35 patients (54.7%) with primary open-angle glaucoma (POAG) and 29 patients (45.3%) with pseudoexfoliative glaucoma (PEG). Group 1 (n = 38) underwent PHACO-GATT, and Group 2 (n = 26) underwent standalone GATT. Data, including intraocular pressure (IOP), the number of anti-glaucomatous medications, and complications, were analyzed preoperatively and postoperatively (1st, 3rd, 6th, 12th, and 24th months). Surgical success was defined as achieving a >= 20% IOP reduction or IOP <= 21 mmHg with or without medications. Results: The mean age was 74.4 +/- 7.2 years in Group 1 and 70.8 +/- 7.3 years in Group 2. Both groups achieved significant IOP reductions at the 24-month follow-up: Group 1 from 28.6 +/- 6.3 mmHg to 12.7 +/- 2.4 mmHg, and Group 2 from 27 +/- 4.8 mmHg to 13 +/- 1.7 mmHg (both p < 0.001). BCVA in Group 1 improved significantly from 0.77 +/- 0.29 logMAR to 0.28 +/- 0.13 logMAR at 24 months (p < 0.001), while in Group 2, it remained stable at 0.46 +/- 0.19 logMAR at baseline and 0.47 +/- 0.19 logMAR at 24 months (p > 0.05). The mean number of anti-glaucoma medications decreased significantly in both groups (p < 0.001) without significant intergroup differences (p > 0.05). Complication-free rates were 68.4% in Group 1 and 69.2% in Group 2 (p = 0.899). Surgical success rates were comparable between groups at 12 (100% in both groups) and 24 months (94.7% in Group 1, 96.2% in Group 2). Conclusions: Both PHACO-GATT and standalone GATT demonstrated comparable efficacy and safety over a two-year period. PHACO-GATT provided significant visual acuity improvements due to cataract extraction, making it a suitable option for patients with coexisting cataracts and glaucoma.