A new phase has been observed during the sodium intercalation of hafnium nitride chloride as intermediate between the host beta-HfNCl and the already reported Na(0.29)HfNCl with Tc of 24 K; the new intermediate shows interlayer spacings ranging from 9.48 to 9.67 A, corresponds to a second stage intercalate of HfNCl and is superconducting with a critical temperature of 20 K.