This study investigates lexical production in Spanish as L1 and L2 in an experimental context. Based on a series of lexical availability tasks, words produced by native and non-native speakers of Spanish are contrasted in relation to test modality, oral or written, and response time. The production of native speakers is characterized by being significantly higher and more accurate, while L2 responses reflect lower lexical competence, the influence of L1 and divergent acquisition patterns. Although previous studies had not found significant differences between the number of responses produced orally and in writing, we find that such differences exist, but that they are conditioned by the response time, which affects differently the production in L1 and in L2, although their evolution describes a similar trajectory in both cases. This methodological factor would also cause the neutralization of the qualitative differences between oral and written responses in both groups of participants.