Corporation Tax Online

  • Sign In
    Use your Katso ID and Password to sign in. You must be a holder of one of the following Katso Roles: Admin or Master User, Parallel Master, or Filer of Income Tax Returns. No login is necessary for the tutorial demo version.

What does Corporation Tax Online do?

You can file an income tax return (complete with all enclosures) for the 2015 and 2016 taxable year in Corporation Tax Online. You make your filing by keying in your input.

If necessary, you can come back later to open a new session to add more enclosures or more details to your filing.

Who may use Corporation Tax Online?

People who are authorised to represent a limited liability company, a cooperative society or a non-mutual real estate company may use it.

Because you are expected to key in your input on every line, Corporation Tax Online does not accept a tax return that an accounting software program has generated. To send us such a return, go to


Corporation Tax Online will accept tax return information for the 2016 taxable year.

Launch the Demo



  • Demo (tax year 2016)

Demo lets you try out Corporation Tax Online and experiment with the figures of a dummy corporation. Tax Administration does not receive any input you enter into the Demo.

More information