Aim To evaluate the epidemiological trends of peritonsillar abscess (PTA) in Australia using open demographic data obtained from the Australian National Hospital Morbidity Database (NHMD). Data contains the age and gender of each PTA admitted care episode that has occurred within Australian hospitals, including data on PTA cases that have required in-theatre surgical drainage. Methodology NHMD data from 1 June 2000 to 30 July 2022 was used for this study. Hospital admission episodes containing the principal diagnosis code for PTA, and in-theatre episodes coded with the procedure code for incision and drainage of PTA were analyzed. Age and gender specific incidences were calculated using Australian Bureau of Statistics (ABS) population data. Results 74,636 PTA admissions and 27,226 PTA in-theatre incision and drainage episodes occurred during the study period. The average annual incidence of peritonsillar abscess was 14.9 ± 1.4 (Mean  SD) per 100,000. A trend increase in both the annual incidence of PTA admissions and in-theatre incision and drainage was observed (Spearman correlation coefficient (Rs = 0.66, [95% CI 0.34-0.85] P < 0.001) and (Rs=0.74, [95% CI 0.46-0.88] P<0.0001 respectively). The male population had an overall higher average annual incidence of PTA admissions (17.4 ± 1.7 per 100,000 versus 12.5 ± 1.3 per 100,000). Age-specific incidence of PTA admissions peaked in the 15 to 19 years age group for both male and female (45.6 ± 5.6 per 100,000 and 44. ± 4.3 per 100,000 respectively). For age groups above 15 to 19 years, the age-specific incidence rate in males consistently exceeded that of females. Conclusion This study shows there has been an overall trend increase in both the rate of PTA admissions and in-theatre incision and drainage in Australia over time. It is of note that the incidence of PTA does not differ between males and females until late adolescent years, with a higher incidence in males than in females observed in the older age groups.