"I don't have" is the grammatically and structurally correct phrase. "I haven't got" seems to be to be a colloquial and incorrect phrase commonly used by kids and non-native English speakers. Eg: "I haven't got any" would be wrong. It should be "I don't have any." However, "I haven't gotten my grade yet" would be correct because it indicates recent past

tangogirl, The "I haven't got" form is less formal; it is more common in Britain. Both forms are correct. The present perfect "have got" is understood to mean the same as the present "to have".... when it is used to express possession of a (thing, relationship, or state) Why? Because one of the meanings of "get" is "to come to have" If you "have come to have a cold.... then you've got a cold...or you have a cold. Examples: Positive........................................................NEGATIVE I have a cottage in the country.................I don't have a cottage in the country. I've got a cottage in the country................I haven't got a cottage in the country. I have a brother.........................................I don't have a brother. I've got a brother...................................I haven't got a brother. I have a cold..............................................I don't have a cold. I have got a cold........................................I haven't got a cold. There is a difference between British and American usage of the participle "got". In Britain "got" is the past participle of the verb "get". It it used to express possession....I've got something. It is also used to form the perfect tenses ...have got ...had got In America two past participles are used with the verb "to get" (got and gotten) In America "have got" is used only for the present tense expression of possession. Example: I've got money........means.......I have money ......or I have money in my possession. I've got my grade.....means ........ I have my grade , etc. For other meanings,the present perfect and past perfect forms of "to get" in America are formed with the participle "gotten". Examples: I get money.......I haven't gotten money......I hadn't gotten money.......(received money) I get my grade......I haven't gotten my grade......I hadn't gotten my grade...received my grade)

In my culture both phrases are equally common. The first on might be slightly more common (I don't have).

A mi me enseñaron que el "Don't have" es ingles americano, y el "Haven't got" ingles britanico.

I don´t have is the academic English, it is commonly used for writting. I havn't got which is more often used in oral communication. Anyway, both means the same. For example: I have to go (Academic English, commonly use in both oral and writting) I gotta go ( American English, commonly used in oral conversation. The scholars called it reduced sounds.)