The tax for an individual earning a taxable income of ₱250,000 in a year is ₱0. In the Philippines, the government exempts every Filipino's first ₱250,000 earnings from tax calculations.
If you earn more than that but less than ₱400,000, you have to subtract ₱250,000 from your annual taxable income and multiply the tax rate applicable to you (in this case, 20%). You can refer to BIR's withholding tax table for your tax rate if you're earning more. Read more