Customer Service Number (CSN)
The Customer Service Number application is no longer available.
We now include ReadyReturn's best features in our other free online filing application, CalFile. Now that CalFile offers ReadyReturn features and more, we no longer offer ReadyReturn, and a CSN is no longer needed.
CalFile is a simple, easy-to-use service that offers free, direct to government e-filing of your tax return. CalFile offers convenient features such as:
Get started with CalFile