quoted from the Kenya Travel Information centre website
"The Kenya shilling is freely exchangeable, and most major facilities accept major credit cards.
The official currency is the Kenya Shilling. The written abbreviation is either KSh or using /= after the amount (ie 500/=). Available Notes are 50, 100, 200, 500 and 1000 shillings. Available coins are 5, 10 and 20 shillings. Visitors to Kenya should change foreign currency at banks, bureaux de change or authorized hotels. The easiest currencies to exchange are US Dollars, Pounds sterling and Deutschmarks. Travellers Cheques are widely accepted, and many hotels, travel agencies, safari companies and restaurants accept Credit Cards. Most Banks in Kenya are equipped to advance cash on credit cards. There are no restrictions on the amount of foreign currency that can be brought into Kenya. Before departure, travellers are advised to convert any excess Kenya shillings into foreign currency at a bank or bureau de change before departure. Departure taxes can be paid in local or foreign currency. Anyone wishing to take more than 500,000 Kenya Shillings out of the country will require written authorization from the Central Bank."