Timed entry slots for Uffizi and Academy galleries?

If you have the Firenze card, you have to call the Firenze call center to book your times with the Uffizi and Accademia or show up to the ticket office with your card. I don't think you can book online. We ended up buying individual since you have to use it alot to make up the cost. We're only doing these 2, which seem to be the most expensive and are about half the cost of the card.

Here's the FAQ on the card, scroll to bottom under "USE".
https://www.firenzecard.it/en/faq?search_api_views_fulltext=uffizi

I almost waited to late to secure our tickets. We are going to Florence in less than month and only couple times were available during our trip. One day was already completely sold out. I wouldn't risk it. I would buy the tickets online and reserve a time. Spending a few extra dollars is better than wasting time in line for hours or missing out totally.

I used the method Joe described above. In March, we bought our firenze cards online, choosing to have it delivered on the phone app. I then called the number as described in the FAQ, followed the instructions and was connected to a person who spoke English very well. I had already decided what times I wanted, and checked on the BTicket site to make sure the times were open, I just gave the woman my requested time and she recited back my confirmation number which I wrote down. Then the morning of each visit, I went to the ticket office of the given museum and gave them my reservation number, showed my Firenze card (on the phone) and they printed out my tickets. It was a lot easier than I expected. Call and reserve your times as soon as possible, but note, they didn't ask me to prove I had already purchased the firenze card when I made the reservation on the phone, only when I picked up the tickets in Florence.