Multicomponent perspectives on second language reading proficiency offer a contemporary understanding of reading and its development (e.g., Yamashita, 2022). In this web-based experiment, we investigated the relationship among L2 reading proficiency measures--reading comprehension, listening comprehension, reading fluency--and component reading skills in English, assessed through tests of vocabulary, grammar, and orthographic knowledge. A sample of 101 L2 learners from a Thai university participated, providing demographic and language background information and completing a survey regarding their motivation to perform well. As expected, reading and listening comprehension were strongly correlated. Moreover, a three-factor model emerged, with word-decoding skills, linguistic comprehension, and word-processing speed as latent constructs explaining just over half of the overall variance in L2 reading proficiency. Notably, component skills in English contributed more significantly to individual variability in reading and listening comprehension than to reading fluency. These findings suggest that while both comprehension and fluency are important facets of reading proficiency, a different set of skills may underlie reading fluency in a second language. The findings are discussed in relation to current theories of reading proficiency, with implications for L2 reading instruction considered.