In Taiwan there has been limited research of epidemiological surveys on prevalence of infertility. This study aimed to provide the updated prevalence of primary infertility and of help-seeking among residents in Taiwan. Between February and March 2023, we conducted a cross-sectional population-based telephone survey of 1,297 men and women aged 20-49 years who were residing in Taiwan. We used computer-assisted telephone interviewing techniques to collect data regarding sociodemographic and reproductive characteristics. Using two approaches to defining infertility, we estimated the prevalence of infertility and the prevalence of help-seeking behaviors. Our analyses accounted for survey weighting. The response rate was 27.9%. Among 1,297 respondents, 829 (63.9%) were married or cohabiting, including 404 men and 425 women. The prevalence of primary infertility using definition 1 was 5.6% (95% confidence interval [CI]: 4.2% - 7.4%); the prevalence of primary infertility using definition 2 was 6.7% (5.1% - 8.6%). Regarding professional help-seeking, 11.1% (9.2%-13.5%) had ever consulted a doctor about getting pregnant; 9.9% (8.1%-12.2%) had ever received diagnostic tests/treatment to help with conceiving; 2.6% (1.6% - 4.0%) were currently receiving diagnostic tests/treatment to help with conceiving. Our nationwide survey of the prevalence of primary infertility in Taiwan suggests that the prevalence was not as high as what is often seen in the news reports (about 14%). These findings also suggest there may be a gap between those who are currently experiencing infertility and those who are currently being treated; hence, we call for raising awareness of infertility and improving access to infertility healthcare.