Abstract Background Little is known about the companion animals which tested positive in Mexico for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. Due to this, it is that we have documented the infection of companion animals, via an exploratory approach in two localities of the Valley of Mexico, in which the companion animal owners tested positive for COVID-19. Methods Oropharyngeal and nasopharyngeal swabs were collected from 21 companion animals. Also, a Reverse-Transcription Quantitative Polymerase Chain Reaction was used to test five probes in three SARS-CoV-2 genes. More than one-third (5/14) of these samples were positive for SARS CoV-2 corresponding to dogs. Results This research translates into the first available report on companion animals with SARS-CoV-2 infection in the most populated area of Mexico. Samples were added chronologically to previous reports prepared in other areas of the country, from February through November 2022. Conclusion Although SARS-CoV-2 infection in dogs is not as common as in other animals, our results suggest that it can be transmitted to dogs by their owners to a greater extent than previously reported.