Tax bill for self employed

My Gran has a carer who is foreign and has not paid tax on her income for the last two years. She's received a tax bill of €12,000 for these 2 years. using Karl Grabe Tax calculator i calculater her tax due to be 4,800 (income of 28,600 PA)

Could the reason for the 12k bill be fines and interest as she has not paid tax in 2 years?

I presume as she is not related to my gran she is classified as self employed.

Karl Jeacle's calculator www.taxcalc.eu is primarily aimed at PAYE workers so the results may not be applicable for self-employed. Your grandmother probably needs professional advice from an accountant or tax expert.

Thanks for response, it is correct tho in saying that self employed are obliged to pay income tax every tax year and will incur fines & interest if they fail to do so?

Self employed are self assessed so must file returns/payments as necessary each year. Failure to discharge any liabilities arising could well lead to interest/penalties.

I have been self employed since 2006 - you don't need to submit accounts until this year; at which point you pay for 2006 based upon income and preliminary tax on 2007 based upon 2006 income + 5%-10%.

€12k does seem very expensive for such a low income. Best advice would be to speak with a qualified accountant. 15th November is the closing date for revenue on line or 31st October otherwise.