All taxpayers must report gains and losses from the sale or exchange of capital assets. California does not have a lower rate for capital gains.The California capital gains tax is levied at the same rate as regular income. This page walks Californians through what they need to know. Line 1 – List each capital asset transaction. Column (a) – Description of property. Capital gain calculation in four steps. Determine your basis. Discover the essential information on California's capital gains tax for 2024 with our comprehensive guide. When you sell stocks, you could face tax consequences.