You may import into the country up to $10000 (or equivalent) without declaring it. You may export from the country up to $3000 without declaring it. 

If you export from the country a sum of money over $3000 and up to $10000 it must be declared on departure. 

If you import into the country a sum of money over $10000 or certain categories of goods such as more costly electrical items, jewellery/antiques and valuable musical instruments you must complete a customs declaration form (available at all ports of entry) on arrival. 

If you are exporting from the country a sum of over $10000 you must provide documentary proof that you either imported it into the country or have legally obtained it whilst in the country. 

If you wish to import certain sophisticated electronic items (e.g. Global Positioning System instruments), you must get an operating licence from the Russian authorities before you travel. If you are unsure whether you should declare an item or need an operating license you should check with the Russian Embassy before your departure. 

If you complete a declaration form you must ensure that it is stamped by a Customs official at your port of entry or it will not be valid. If you fail to complete a declaration form on arrival or to get it validated by Customs officials your foreign currency and non-declared items may be confiscated when you leave Russia and you may be fined.