你說step up是聯邦增值稅的成本，又不是加州地稅的問題。

看文章看錯了。

加州地稅重估，有很多exception，自住房一個配偶死後給另一個配偶，不觸發地稅重估。

https://www.boe.ca.gov/proptaxes/faqs/changeinownership.htm#constitutes?

 

• Transfers of the principal residence between two cotenants that occur upon the death of one of the cotenants, provided that:
  • The two cotenants together owned 100 percent of the property as tenants in common or joint tenants.
  • The two cotenants must be owners of record for the one-year period immediately preceding the death of one of the cotenants.
  • The property must have been the principal residence of both cotenants for the one-year period immediately preceding the death of one of the cotenants.
  • The surviving cotenant must obtain a 100 percent interest in the property.
  • The surviving cotenant must sign an affidavit affirming that he or she continuously resided at the residence for the one-year period preceding the decedent cotenant's date of death.