Two honest ways through winter
A Russian tortoise in a northern home faces a winter far longer than the one his species naps through in the wild, and there are two legitimate plans — choose one, deliberately. He can hibernate under controlled cold, the traditional route for this hardy species; or he can overwinter awake indoors, in a heated, lit tortoise table, eating and basking through to spring. What is not a plan is drift: a tortoise left in a cold, dim room with no heat and no preparation gets the dangers of both routes and the benefits of neither, and it is how most winter losses happen.
If he hibernates, preparation is the whole job
Hibernation is only for a tortoise who is healthy, well-grown and has eaten well all season — a vet health check first is the established advice, because a tortoise carrying illness or parasites into the cold may not come out of it. Over the weeks before, food is tapered so he goes down with an empty gut, and regular lukewarm soaks keep him hydrated. The hibernation itself needs steady refrigerator-level cold, around 38–41°F, in a secure, ventilated box — a fridge used for nothing else is the common method — because a garage or shed that swings between frost and mild spells keeps waking him and dropping him cold again. Weigh him weekly, in the box, quickly: the whole method stands on those numbers.
If he overwinters awake
The indoor table needs to reproduce a good summer day: a basking spot of 95–100°F, UV light for ten to twelve hours, a cool end he can retreat to, and enough space and substrate depth to dig and patrol. He should keep eating his leafy, weedy diet through winter, with regular soaks since indoor heating dries tortoises as surely as it dries snakes. An awake tortoise who stops eating, or whose nose runs or eyes swell, is not settling in — he is a vet case. Many first-year keepers choose this route while they learn their tortoise, and there is no failure in it; a well-kept awake winter beats a badly run hibernation every time.
The numbers that end a hibernation early
On either route, weigh weekly and write it down. During hibernation, a tortoise should lose weight very slowly; one who drops weight quickly, urinates in the box, or has been down far longer than planned gets warmed up gradually and seen by a vet — those are the stop signals, not inconveniences. After waking, expect drinking and basking before eating, and appetite within days; a tortoise who will not eat a week after waking, or wakes with a runny nose or swollen eyes, goes to the vet rather than back in the box. A winter this dependent on records deserves real record-keeping, and his KinsLe Pet Passport keeps the weekly weights, soak notes and vet paperwork together in one portable packet.