Tax Paying Form BIR51/BIR52: Are Blank Spaces Allowed? Posted byadmin December 27, 2013 Leave a comment on Tax Paying Form BIR51/BIR52: Are Blank Spaces Allowed? The question is: if you have no data to complete an item on the form, is it possible to leave it blank? – No. You MUST complete all the items. So, in case there is no information to report – just write in “0”.