Ideally, you should complete your renewal form with the figures entered from your tax return for the last tax year, i.e. year ended 5th April 2013. This will ensure your tax credits award is as accurate as possible.
However, if you have not yet completed your accounts and tax return for the most recent tax year, you may submit estimated figures to the Tax Credit Office. This must still be done on the renewal forms and by 31st July 2013 as normal.
You must supply the Tax Credit Office with the actual figures as soon as possible though- and no later than the 31st January 2014.
If you would like to discuss this in more detail, please feel free to contact us to be put in touch with your local TaxAssist Accountant.