Lexical variation abounds in New Zealand Sign Language (NZSL) and is commonly associated with the introduction of the Australasian Signed English lexicon into Deaf education in 1979, before NZSL was acknowledged as a language. Evidence from dictionaries of NZSL collated between 1986 and 1997 reveal many coexisting variants for the numbers from one to twenty in NZSL. This article reports on an empirical investigation of how the use of variants for numerals is associated with social factors of age, region, and gender. Results confirm that age group is the strongest factor in variation and that region also plays a role. The analysis of illustrative cases of number variation reveals sociolinguistic processes of social differentiation and changing lexical usage in the NZSL community. Findings provide comparative data on aspects of number variation reported in the closely related British Sign Language. (Contains 10 tables and 2 notes.)