carry sth back
phrasal verb with carry verb [ T ] uk/ˈkæri/ us
ACCOUNTING
to copy an amount of money on an earlier page or column of an account, or to move it to an earlier accounting period:
carry sth back to sth Companies operating at a loss can carry back current losses to periods in which profits were made to get a tax refund.
You have until January 31 to carry back pension contributions to the previous tax year and claim unused tax relief.