Mostly 3, but as many as 4.
One in the little pocket of my 5.11 boots, one in my right front pocket, and a fixed blade iwb on my 9 o'clock position. I also carry an XD45 iwb on my 4 o'clock position.
The knives I rotate right now are a Spyderco Yojimbo 2, Strider SMF Tanto, Spyderco Tenacious, Spyderco PM2, and Ratmandu. The fixed blade never changes, and it never will. The Ratmandu is outstanding.