At 799 you qualify for the best rates already. Getting into the 800s won't get you a better rate. 
I am assuming that this is the mid score of your 3 FICO scores. If the score is from some other vendor, then my answer is different.
@bostonbean wrote:I'm hoping to qualify for a mortgage (30 year jumbo) in the next few months, and my current FICO is 799. Is there any benefit in trying to get it higher? Is there a new tier of lower rates if I break 800?
As for my score, it seems like the major factor counting againt me is my credit utilization (at 14%). I only have credit cards on my report, and I actually don't carry a balance on any of my cards. But I travel a lot for work, so I normally spend ~$3500 a month on my card, and pay it off each month. If I were to a) shift this spending to my debit card or b) start making an extra payment a few days before my statement date, would that help me?
Welcome to the forums!
+1 to what SO stated.
Beyond that, the highlighted may help you but probably not that much as 13% reported utilization isn't terrible to begin with. Personally I'd not move spending to a debit card but you could do so in a pinch if needed (like the final month pre-mortgage app just to be *sure*, I do this with a charge card personally but I wouldn't recommend getting one in the run-up to a mortgage).
The general rule of thumb is to let one card report between 1-9% of that tradeline's balance, and have the rest of the cards report 0. Seems to work for most people for close to best possible. That's accomplished by making payments a few days before the statement date, and using some other card in the interim. Lots of information about that on this forum especially in the Credit Cards forum and similar, but I don't think there's any mortgage lenders with tiers above 740 and likely some at 720 in the jumbo space. Least Chase had their advertised rate tier at a 720 for a jumbo 30 fixed when I chatted with them the other day. Other lenders, mileage will vary.
