Background:
The widespread use of the Internet has significant effects on loneliness and interpersonal competence among young adults. This study examines the relationship between Internet addiction levels, loneliness, and interpersonal competence.

Material and methods:
The cross-sectional and quantitative study was conducted among 339 young adults studying at a foundation university. Data were collected using the Personal Information Form, the Internet Addiction Scale (IAS), the UCLA Loneliness Scale (UCLA-LS), and the Interpersonal Competence Scale (ICS).

Results:
The participants’ average IAS score was 43.08±14.79, indicating a “probable addiction” level. The average UCLA-LS score was 50.80±8.34, indicating a moderate level of loneliness, while the average ICS score was 138.79±31.29, indicating a moderate level of adequacy. Gender, income status, and daily Internet use were associated with differences in IAS and ICS scores, with effects falling within the small-to-moderate magnitude range. A weak positive correlation (r=0.127) was found between IAS and UCLA-LS, while a moderate positive correlation (r=0.442) was found between UCLA-LS and ICS.

Conclusions:
These findings highlight the importance of considering the magnitude of associations when interpreting the relationships among the variables. In this sample, higher Internet addiction levels were weakly associated with greater loneliness, and loneliness showed a moderate positive association with interpersonal competence.