My MAGI is pretty high, not much less than the maximum to get a subsidy, so my annual HC contribution (which is a percentage of the MAGI) and the SLCSP are pretty close together. While I can make a pretty good guess as to what the SLCSP will be once the 1095-A form comes out, it isn't a number I can really know for sure until it does come out. For 2016, it ended up being a little higher than my estimate, so my subsidy was a little higher than predicted. Then again, I had a large cap gain distribution at the end of 2016 which made my MAGI rise and subsidy drop. These two unexpected differences offset each other somewhat so I will end up having to repay about $60 in excess advanced premium subsidy.