Should I use American or British English in the IELTS Speaking test?

In the IELTS Speaking test, both British and American forms of English are correct. This means that using American vocabulary is fine, and using British vocabulary is also fine.

For example, you could say "governments should invest in infrastructure like highways and railroads." (AmE) or you could say "governments should invest in infrastructure like motorways and railways." (BrE).

But try to be consistent. Try not to mix the two forms during the test, i.e. if you decide to use American vocabulary, try to use this form throughout the whole test.

This also includes American and British pronunciation. For example, words like 'advertisement' and 'tomato' are pronounced differently in the two forms of English, but both are correct. Again, try to be consistent.