This study aimed to explore instructional practices used to teach words with irregular spelling patterns by Spanish-speaking teachers in 2nd and 3rd grade of elementary school. A sample of 320 teachers from Guatemala, Ecuador, and Spain answered an online survey, which included the Spelling Instructional Practices Scale. Item Response Theory and Confirmatory Factor Analysis were used to analyze the construct validity and reliability of the Spelling Instructional Practices Scale. Results pointed out adequate fit indexes of the proposed models. Spelling instructional practices used by teachers were finally grouped into three factors. Results indicated that Spanish-speaking teachers teach irregular spelling words using a combination of instructional practices. Differences in the informed use of spelling instructional practices according to the teachers' home countries were explored. Significant differences were found between Spanish and Latin-American teachers in the reported use of those instructional practices based on memorization and some materials to teach spelling. However, most teachers reported following a similar pattern when teaching irregular spelling to their students. Limitations and directions for future research are described.