Will the withholding tax rates to be used for doctors/consultant who submitted sworn declaration and signified to be taxed at 8% income tax rate differ from those opted the graduated income tax?

No. The withholding tax rate for doctors/consultants who submitted the sworn declaration (Annex B-2 of RR 11-2018) shall be 5%, regardless of whether they are availing of the 8% income tax or the graduated income tax rates. If the income payer/withholding agent, however, is a government entity, it shall also withhold business tax if the payee selected to be taxed using the graduated income tax rates.