In this article, we have proposed a large negative dispersion coefficient and highly nonlinear polarization maintaining single mode square photonic crystal fiber. The proposed design is extremely attractive for compensation of chromatic dispersion of − 1052.60 ps/(nm km) to − 2421.90 ps/(nm km) around 1340–1640 nm wavelength band. Guiding characteristics are investigated applying finite element method containing perfectly matched layer boundary condition. Simulation outcomes ensure the possibility of large negative dispersion coefficient and low confinement loss of − 2015.30 ps/(nm km) and 3.41 × 10¹ dB/m respectively, at 1550 nm wavelength. The proposed fiber also exhibits highly nonlinear coefficient of 99.73 W⁻¹ km⁻¹ at the same wavelength. Moreover, V parameter assures the single mode operation of the structured fiber over the whole band of interest. The structural diameter variation of ± 2% over the optimum value is simulated and reported to explore the practical feasibility. Besides, effective area is also presented and explained. From overall investigations, it can be reported that the proposed fiber will be an attractive candidate in high-speed transmission system for broadband dispersion compensation, nonlinear optics and sensing applications as well.