In this paper, the transverse resonance technique is employed to calculate the cutoff wavelength of the dominant mode in elliptical waveguide for the first time. Numerical results are given and verified for various eccentricities. The impact of the number of step junctions for the approximation of the elliptical boundary line is discussed. Compared with other methods involving Mathieu functions, the technique is simple, fast, accurate and easy to understand. The method can also be applied to other guide structures and field modes with slight modifications.