Finite two-dimensional (2d) polymer photonic crystal (PC) slab waveguides were fabricated from a benzocyclobutene polymer on a low refractive index substrate from Teflon. Square and triangular air hole lattices were realized by electron beam lithography and reactive ion etching. Polarization and wavelength dependent transmission measurements show TE-like and TM-like stop gaps at 1.3micrometers excitation wavelengths and are in good agreement with the calculated data obtained by 2D and 3D finite difference time domain (FDTD) methods. Transmission was suppressed by 15dB in the center of the TE-like stop gap for a PC length of only ten lattice constants. Defect states were induced within the stopgap by lattice modification and theoretically and experimentally characterized.