Soil looks wet, too dense and the pot is too large for the tree.

Hey thanks for the reply. I just watered it today and I moved it into the 3 gallon about a week ago because it really needed to be repotted from the small container it was in. The leaves had already been dropping so I figured it would help.

When you repotted, you covered the tree above it's started normal soil line since there are multiple branches coming up through the soil line. That would cause a problem - citrus bark will rot out. Pull the soil back or raise the tree up.

Okay thanks! I will try both of those things.

And check it carefully for signs of insects -- white residue or black dots on the branches

Yeah I'm not seeing anything bug wise. Its just weird to me how it was doing so well with all new growth and then just took a turn for the worse. Right now the entire tree is brown and bare wood.

The tree is shocked from repotting. Maybe you also changed its position with regards to light and temperature? Citrus trees can quickly shed their leaves when in shock. Do as the others have advised.

I'm with Pip....That pot is way to big for that tree in such a dense mix...No tree should drop all their leaves when re potted, even bare rooted any time of the year..Shock is usually caused from operator error, especially at the worst time of the year as Nikthegreek mentioned..

May I ask a question and it's important that you remember this..Have you ever once let the leaves get to a wilt in that small pot? Did that mix ever dry out before you caught that it needed a watering? Did it catch you off guard..It usually happens in a sunny window when the mix is in a small pot...

Keep in mind that that pot might be borderline for that tree when it had leaves but once it looses all leaves it has no way to use the water and it just stagnates.

Yeah that would make sense regarding pot size with no leaves left. I had it outside all summer in about a 1 gallon size pot which constantly dried out to a crisp everyday causing the leaves to wilt at about mid day. I would water it in the morning along with all of my garden and it did excellent. Tons of growth and not a single issue. Does it actually have a chance to come back from this? Just curious what you guys would think. Is it a lost cause at this point?

It still has green, I think it still has a chance. But I am an optimist ;) Keep it on the dry side and give it as much light as possible. Hopefully that will have it sprout some leaves once that happens cut back the obviously dead branches. Also if you haven't already raise the graft line above the soil.

Sounds like it should have been repotted last summer. That was just too much drying out for it. It needs lots of light. Do you have in a bright window?

That's what I figured.You have killed many roots and now it's catch up..Just watch your watering and give it as much sunlight as it should have as suggested by many..DO NOT FERTILIZE, at least I would never until you see a good amount of new growth at least in inch or longer..