The main purpose of this study was to examine the effects of teachers’ written corrective feedback (hereafter WCF) on first-year university students’ writing achievement. Theoretically, however, various theories and hypotheses firmly support the role of corrective feedback (hereafter CF) in L2 writing classrooms its role in the form of negative evidence is highly underscored in the noticing, output, and interactionist hypotheses, which are the front-runner hypotheses that underpin and underscore the role of CF in L2 classes and improve their writing achievement. On practical grounds, the existence of diverging viewpoints on the role of WCF in L2 classes motivated this investigation. Thus, to achieve the study’s main purpose, a pre-test-post-test quasiexperimental non-equivalent comparison group design involving a self-descriptive paragraph writing test as the data-gathering tool was used. To this end, three intact classes of first-year Debre Tabor University students were selected, of which two were experimental groups and one was a comparison group. In light of this, the pre-test was given to all groups at the outset of the study, mainly to assess the learners’ prior language proficiency. All participants in the three groups were given an immediate post-test following the intervention with the learners in the experimental groups. A moderately delayed post-test (hereafter delayed post-test) was given to the participants in all three groups after the intervention was given to the experimental groups on the papers submitted for the immediate post-test. The results from a one-way ANCOVA revealed that WCF is a viable pedagogical tool for enhancing first-year university students’ writing achievement. Thus, the results of the study showed that both experimental groups outperformed the comparison group in both post-tests, implying that written CF plays a key role in helping learners improve their writing abilities. Furthermore, the findings of the study indicated that learners in the direct group who received direct WCF with metalinguistic explanations outperformed their peers in the indirect group, who were given only indirect WCF, and in the comparison group, who received no feedback. Based on the findings of the study, it was inferred that WCF is an essential pedagogical tool that supports EFL first-year students in improving their writing achievement. Based on the conclusion, the teachers are recommended to apply both direct accompanied by metalinguistic explanations and indirect WCF in EFL writing classes. Mostly, direct accompanied by metalinguistic was found to be the best provision strategy WCF; thus, teachers are encouraged to apply in favor of it. Keywords: Feedback, written corrective feedback, sustained feedback, EFL first-year university