Paying for National Park Entry
From 2017, Kenya Wildlife Service (KWS) national parks and national reserves are no longer allowed to accept cash as payment for entry. Payment has to be made via credit card or m-Pesa (mobile-phone-based money transfer). If you only have cash, you can get a bank deposit slip from any Standard Chartered or Kenya Commercial bank.
We found that at some of the smaller parks you can still pay cash (particularly if the card machine is not working, which happens often), though it is better not to take the risk.