A non-filer is someone who does not file a tax return by the required due date. They may be subject to penalties such as interest and late fees. The Federal Board of Revenue in Pakistan specified that non-filers will have their withholding taxes doubled under a new law. Withholding tax refers to a tax deducted from income payments by the payer and paid to the government on behalf of the recipient. It may be treated as a partial payment of the recipient's total tax liability.