American spelling uses -ize for words like civilize and organize (and all variants and derived words). British spelling uses either -ize or -ise and may vary from one publication to the next.
But whichever you choose, you should be consistent. Mixing the spellings so that you’re organizing your organisation is seen as poor style.
- Many Dutch people seem to have been taught that British English requires the -ise form: that’s incorrect. A specific publication may have that as its house style, though.
- Rest of the world is generally -ize.
- So it’s easiest to stick to -ize except when specifically asked not to.
- Exceptions: when citing someone else or listing a title in a bioliography or references section or giving the name of an organization, you should leave it as-is
A note while we’re on the subject: -yse and -yze is different. The Brits never write “analyzed” or “paralyzing” or “breathalyzer”. Not that there are many of those – outside the scientific world, it’s pretty much only those three.
Prevalence: moderate. It’s just a question of spell-checking and searching (e.g. for isation, ise and ising). But it happens a lot.
Frequency: common. In a text of any length, it’ll turn up a few times.
Native: yes. Oh yes, we do it too. Particularly the Brits. Especially with the advent of computerized tools and translation memories – it’s easily done!