Once, very few places in Russia expected you to tip; now it is increasingly common. Top-end hotels and restaurants in Moscow and other large cities add a 10-15 percent service charge.
If that’s not in evidence, 10-15 percent per cent is a customary tip in these places, depending on the service. If paying by credit card, never add the tip to the bill but leave cash. There are tax issues that would complicate a pay out to waiting staff.
Tips for porters, room service and house-keeping in hotels vary from the equivalent of $1-5.
Tipping is not considered customary for taxi drivers but you can round up the fare. In fact, you should negotiate and settle upon your fare before you get in.