The cricothyroid (CT) space is the interval between the anterior inferior border of the thyroid cartilage and the anterior superior border of the cricoid cartilage. It is well documented that the CT space opens and closes with changes in pitch, narrowing with rising pitch and widening with falling pitch. Previous studies have suggested that the CT space is the most important anatomical dimension of the larynx in determining vocal range. Further, in excised larynges from cadavers it was shown that a nearly linear relationship exists between vocal pitch and CT distance. This study investigates the relationship between the anterior height of the resting CT space measured using ultrasound and performance vocal range in female singers. Potential associations with and between voice categories (soprano and mezzo-soprano), age, ethnicity, anthropometric indices (weight, height, BMI), neck dimensions (circumference and length), laryngeal dimensions (anterior thyroid and cricoid cartilages heights) and speaking fundamental frequency are also explored.