For gorilla permits specifically: 6-10 months ahead, non-negotiable if you want a specific date and sector. Uganda Wildlife Authority sells a fixed daily allocation per gorilla family, and the popular Bwindi sectors (Rushaga, Buhoma) sell out well ahead of peak season (June-September, December-February). For the safari portion generally, 4-8 months ahead gives you the pick of camps during migration season and school-holiday periods; 2-3 months is often still workable in the November-May shoulder season, when availability is far less constrained. The exception that catches people out: hot air balloon safaris and specific luxury camps with fewer than ten rooms sell out even further ahead than the permits do, because supply is genuinely tiny. Our rule of thumb — if your trip includes gorilla trekking, Christmas/New Year, or a named luxury camp you have specific reasons to want, book 8+ months out. If it is a flexible mid-range Kenya-Tanzania safari in the June-October or January-March windows, 3-5 months is realistic. Deposits are typically 20-30 percent to hold space, with balances due 60-90 days before travel.