The European Union and the United States passport holders can get a visa on demand at the point of entry for entering South Africa. But note that the expiry date of the passport must exceed at least one month the date set for the end of the stay in the country. However, bare in mind that the passport must have blank pages face to face for the stamp of entry and exit of South African territory.
Allow at least three clear pages for stopover flights. Note, in the event of travelling to other African countries (Botswana, Malawi, Mozambique, Namibia and Zambia) the passport must be valid six months after the set date of the return (not one month as above). if you are travelling with your children they must have their own passports.