This guidance provides an updated plan for Californians to gather outside their household and replaces the March 16, 2020, October 9, 2020 and other prior gatherings guidance. It applies to private gatherings, and all other gatherings not covered by existing sector guidance are prohibited. It also applies to activities protected by the First Amendment to the extent that they are not already permitted by other guidance, notwithstanding any guidance, orders, or directives to the contrary. Gatherings are defined as social situations that bring together people from different households at the same time in a single space or place. When people from different households mix, this increases the risk of transmission of COVID-19.
All persons planning to host or participate in a private gathering, as defined above, must comply with the requirements identified below and are strongly encouraged to follow the recommendations as well. Activities protected by the First Amendment may proceed under this guidance notwithstanding any guidance, orders, or directives to the contrary. Local health jurisdictions may be more restrictive than this guidance. Refer to your local guidance for what is allowed in your area.
a. Gatherings that include more than 3 households are prohibited. This includes everyone present, including hosts and guests. Remember, the smaller the number of people, the safer.
 See, e.g., Hiroshi Nishiura, et al., Closed environments facilitate secondary transmission of coronavirus disease 2019 (COVID-19); Hu Qian, et al., “Indoor transmission of SARS-CoV-2” [pre-print] published in medRxiv on April 4, 2020.
 See Planning Scenarios.
 See, e.g., Report 3: Natsuko Imai et al, WHO Collaborating Centre for Infectious Disease Modelling, MRC Centre for Global Infectious Disease Analysis, J-IDEA, “Imperial college London, UK. Transmissibility of 2019 -n-CoV).” See also Inglesby T B JAMA Public Health Measures and the Reproduction Number of SARS-CoV-2. JAMA Network.2020.7878 (May 1, 2020).
 Transmission of SARS-CoV-2: implications for infection prevention precautions.
 See Preventing the Spread of the Coronavirus