https://my2020census.gov/. Census forms mailed in must be postmarked by October 15 to be counted.Dissenting from the decision of her judicial colleagues, Associate Justice Sonia Sotomayor said those who filed suit against the Trump administration, including several mayors, would "suffer substantial injury" by allowing the census bureau "to sacrifice accuracy for expediency."San Jose Mayor Sam Liccardo, who was a signatory on the lawsuit to extend the deadline for the census, cited Sotomayor's dissent in his response to the high court's decision."A census count delayed is a census count — and justice — denied," he stated.