Your Customer Service Number (CSN) is your key to accessing your personal tax information online.
Need more information? Check out our Frequently Asked Questions.
We issue a new CSN to every taxpayer each calendar year. The number is only valid during the year for which it is issued.
You will need the following to get your CSN:
- Your social security number.
- A copy of your original 2008 California tax return. (If you didn't file a 2008 California return, click here for information about getting your CSN.)
- The California Adjusted Gross Income (AGI) from your 2008 tax return. (Use the chart below to find the line numbers.)
Form Number Line Numbers Form 540 2EZ Line 16 Form 540A Line 17 Form 540 Line 17 Form 540NR (Long) Line 21 Form 540NR (Short) Line 21
- A compatible browser and operating system. We recommend that you log out and close your browser when you are done to ensure the highest level of security.
When using our website, we recommend using one of the browsers listed below.
These browsers support 128-bit SSL encryption, which we use to protect your privacy on our site. Your browser must support 128-bit encryption to use our online services.
Note: FTB's online services may not work in the AOL browser. If you use AOL and experience problems, connect as you normally would, launch another browser (such as Internet Explorer or FireFox), then access the service again.
