Background <p>Respiratory tract infections (RTIs) are a common reason for seeking primary health care services and are one of the main reasons for antibiotic prescriptions in primary care. The COVID-19 pandemic impacted migrants differently from the majority population in Norway.</p> Objectives <p>To investigate the likelihood of antibiotic treatment for RTIs in primary care before and during the COVID-19 pandemic, and types of antibiotics used, for selected migrant populations and Norwegian-born, in Norway.</p> Methods <p>Observational study on adults from Norway, Poland, Somalia, Sri Lanka, and Syria, using primary health service and demographic data from individually linked registries from Norway 2018–2021. We compared the pandemic to the pre-pandemic period using modified Poisson regression to estimate the relative risk of antibiotic treatment for RTIs during the COVID-19 pandemic.</p> Results <p>The relative risk, with confidence intervals in parentheses, of antibiotic treatment for RTIs during the pandemic, by country of birth, was 0.51 (0.51–0.52) for Norway, 0.45 (0.43–0.48) for Poland, 0.41 (0.38–0.45) for Somalia, 0.45 (0.40–0.50) for Sri Lanka, and 0.54 (0.49–0.58) for Syria. Phenoxymethylpenicillin was the most common antibiotic for RTIs, accounting for 48.5–65.3% of treatments, depending on country of birth.</p> Conclusion <p>All groups, irrespective of country of birth, had approximately half the antibiotic treatment rate for RTIs during the pandemic, compared to the pre-pandemic period. The most used antibiotic type was phenoxymethylpenicillin, and the distribution of antibiotic types was relatively stable over time, for all countries of birth. </p>