Microplastics are widely recognized as a category of emergent pollutants that can cause complex ecotoxicological effects. Synthetic fibers released during the washing of textiles are a relevant source of microplastics, which reach aquatic ecosystems from sewer discharges, even when there is retention in wastewater treatment plants. In this paper, we determined microfiber emissions from washing of textiles in a domestic environment, by collecting wastewater from washings of a mix of clothing from a household of 4 people. It is the first time the characterization of microplastic emission from textiles washing is performed in real household conditions. Results estimated an average emission rate of 18,000,000 synthetic microfibers for a reference load of 6 kg of synthetic fibers. Only 7% of the synthetic fibers found were larger than 500 μm in length, 40% were between 100 and 500 μm, and 53% were between 50 and 100 μm.