ABSTRACT The animal feed industry is continuously researching new feed additives to substitute other materials, reduce costs, or add value to the final product. The microalgae Arthrospira maxima, cultivated using wastewater as a nutritional source, was evaluated as a feed additive by including 2, 4, and 6% in isocaloric and isoprotein diets for laying hens. Five replicates per treatment with 5 hens per cage were used during an experimental period of 28 days. Productive behavior and egg characteristics (quality, fatty acid profile, cholesterol level) were evaluated. The inclusion of microalgae up to 4% in diets for 52-week-old laying hens did not affect productive performance (egg production, egg weight, egg mass, FCR, shell thickness, and Haugh units). No effects were observed on the cholesterol level or the concentration of fatty acids in the eggs, but more information is needed to determine if the microalgae drying or storage process can generate variations of these results. The inclusion of 6% microalgae produced an acceptable egg yolk color for the local market. The results indicate that this material can be used as a protein source up to an inclusion of 4% in the diet, and hens may need an adaptation period to maintain production at the 6% inclusion level.