The Riverside County tax assessor reassess the value of a property after it is conveyed to a new buyer, within 2 years of purchasing. In the event the reassessed value is higher than what you paid at closing escrow on a new home purchase (which would be based on the sales price), then a supplemental tax bill is sent to you for the difference to be taxed. If you've had your home for a while and the neighborhood was reassessed, especially due to growth and upward pricing, your taxes will increase. To dispute it, you must contact the tax assessor. Owning a home will always have you paying taxes, even when the loan is completed. You must accept that. Besides...your property taxes may be deductable from your income taxes. Check with your tax accountant or attorney.