Registration in Russia
All of non-resident tourists, who come to the Russian Federation, should be registered at the Federal Migration Service in a town or a region, where they stay for seven days since the day of their arrival.
If you travel with a visa and stay at a hotel, one thing you need – to show your migration card and passport to the hotel staff, who carries about your registration, which is done on the first day of your arrival.
Also if you rent a flat with the help of the agency, you need to turn to the agency for receiving registration according to the place of your temporary residence. If you travel with a business visa, the company invites you and is responsible for your registration. You may be registered at Department of Migration and Citizenship or at any post office branch. To make registration at the mention places you need to show your passport and migration card to the staff of the establishments.
If the agency or the hotel staff refuses to register you because of some reason (in spite of their legal obligation) you may always be registered at the agencies in big cities, but they will do it for an extra fee.