If you need to amend your California resident income tax return, complete an amended Form 540 and check the box at the top of Form 540 indicating AMENDED return. Attach Schedule X, California Explanation of Amended Return Changes, to the amended Form 540. For specific instructions, see “Instructions for Filing a 2021 Amended Return”.
The CA amended returns can now be e-filed for the current tax year (2021), when e-file is available.