How far in advance of arrival may you apply for a Kenya transit visa??

How far in advance of arrival may you apply for a Kenya transit visa??
You'd normally just get it on arrival like a regular tourist visa, but if you know you'll be transiting through Nairobi and need one, then I think up to three months ahead. But frankly you might as well wait till you arrive - same price, no postage or collection, no photos needed.
Richard
Purchase on arrival @ USD$20/person... good for 24-48/hrs only.
If later returning to Kenya, especially by road or even air and remaining in country, you'll require another Transit or Regular Visa depending on return length of stay. If returning to Kenya direct into the International/JKIA airport for homebound flight, you won't need another Visa as you'll be an 'in-transit' pax and cannot leave the secure area and/or airport.
If need for Transit Visa is for entry then to Tanzania, remember that you'll require a Yellow Fever inoculation and proof of same for entry. And if you happen to be heading to Zanzibar/ZNZ, you will also require the YF inoc and proof of same.
Edited: 4:36 pm, August 09, 2012hi am flying to zanzibar via kenya, will be in transit. Do i need a kenyan visa ?
If you are not leaving the airport and stay 'airside' you do not technically enter the country so do not need a visa