I don't know what is taking HCAD so long to update the tax rates, but I needed to calculate my bill come next January. All tax rates are posted online from the various districts..
District - 2013 Rate per $100 - 2014 Rate per $100 - Homestead Exemption
HISD - 1.1867 - 1.1967 - $15k + 20%
Harris County - 0.41455 - 0.39135 - 20%
Flood Control - 0.28270 - 0.02658 - 20%
Port of Houston - 0.01716 - 0.01614 - 20%
Hospital District - 0.17000 - 0.15989 - 20%
Education Dept. - 0.006358 - 0.0059999 - 20%
Houston Community College - 0.097173 - 0.090554 - 10%
City of Houston - 0.638750 - 0.603431 - 20%
District - 2013 Rate per $100 - 2014 Rate per $100 - Homestead Exemption
HISD - 1.1867 - 1.1967 - $15k + 20%
Harris County - 0.41455 - 0.39135 - 20%
Flood Control - 0.28270 - 0.02658 - 20%
Port of Houston - 0.01716 - 0.01614 - 20%
Hospital District - 0.17000 - 0.15989 - 20%
Education Dept. - 0.006358 - 0.0059999 - 20%
Houston Community College - 0.097173 - 0.090554 - 10%
City of Houston - 0.638750 - 0.603431 - 20%